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973 Cards in this Set

  • Front
  • Back
Substances that dissolve in water are called:
hydrophilic "water loving"
Substances that lack charged poles, nonpolar covalent substances do not dissolve in water and are called:
hydrophobic "water fearing"
True or false, water has a high heat capacity?
T or F, ice is more dense than water
True or false water has strong cohesion and high surface tension:

What intermolecular force causes this?

Give an animal example
True: Cohesion, or attraction between like substances, occurs in water because of the hydrogen bonding between water molecules.

Water bugs exerts less surface tension than what is on the water. That is why they can walk
True or false...water adheres to other molecules?
In water, what is the difference between cohesion and adhesion?
Cohesion, or the attraction between like substances, occurs in water because of the hydrogen bonding between water molecules.

Adhesion, is the attraction of unlike substances.
What is capillary action?
water rises up the tubing or creeping through the paper. An example is in organic chemistry during TLC (Thin Layer Chromatography)
What are polymers?
molecules that consists of a single unit (monomer) repated many times
What is a monomer?
A single molecule unit.
True or false, carbohydrates are made from sugar molecules?
What it the simplest kind of carbohydrate? define it and give examples of it
it is the simplest kind of carbo. It consists of a single sugar molecule.

Examples, are fructose or glucose
Sugar molecules have the formula:
(CH2)n, where n is any number from 3 to 8
What is this?
What is this?
Beta Glucose
What is this?
What two monosaccharides make this molecule? what is it? What is this commonly known as?
glucose + fructose = sucrose
Table Sugar
What is this? And how is it made?
Starch. It is a polymer of alpha-glucose molecules. It is the principle ENERGY STORAGE molecule in plant cells.
WHat is starch?
a polymer of alpha-glucose molecules. It is the principla energy storage molecule in PLANTS
Def. glycogen?
is a polymer of alpha glucose.

It differs from starch by its patter of polymer branching. It is a major storage molecule in ANIMAL Cells.
def cellulose?
is a polymer of Beta-glucose.

It serves as a STRUCTURAL molecule i th weall of plant cells and is the major component of wood.
def chitin
is a polymer similar to cellulose, but each Beta-glucose molecule has a NITROGEN containing group attached to the ring.

Chitin serves as a STRUCTURAL mol. in the walls of FUNGUS cells and in the exoskeltons of INSECTS, other ARTHROPODS, AND MOLLUSKS.
What type of glucose is only for humans? And what type of glucose is only specialiezed organisms like the bacteria and protozoa in the guts of termites?
Alpha-Glucose for Humans/Animals

Beta-Glucose for specialized organisms
What three groups are carbohydrates classified in?
1) monosaccharides
2) Dissaccharides
3) Polysaccharides
What class of substances are insoluble in water but are soluble in nonpolar substances?
What are the three major groups of Lipids?
1) Triglycerides
2) Phospholipid
3) Steroids
Fats, oils and waxes are in what group?
What is this and what does each row represent (top down)?
A triglyceride
Top = saturated fatty acid
Middle = monosaturated fatty ac
Bottom = polyunsaturated fatty acid
How are tryglycerides made?
Glycerol + 3 Fatty Acids
What are fatty acids and why are they called that way?
Fatty acids are a carboxyl group (-COOH) , the acid part.

Fatty = from how long the carbon chain is on the carboxyl group.
When the fatty acid on the triglyceride is all covalently bonded and has no double bonds it is said to be a
saturated fatty acid
A fatty acid that has one double covealent bond in a triglyceride it is a
monosaturated fatty acid
When a fatty acid has two or more double bonds it is said to be
What is a phospholipid?
It is just like a triglyceride except that one fatty acid is replaced with a phosphate group (-PO3^-2)
What is this a structure of? And why are they labled hydrophbic and hydrophilic?

The hydrophilic is the head because it is polar, which means this side will point towards water

hydrophobic becase the fatty acid tails are non-polar and don't like water. they point in the towards the cell.
What is an amphipathic molecule and what is an example of one?
def: the moecule has both polar (hydrophilic) and non-polar (hydrophobic) regions.

Example: phospholipid
How are phospholipids usually found? What do they usually form?
They are often found oriented in sandwichlike formations with the hydrophobic tails grouped together on the inside of the sandwich and the hydrophiic heads oriente toward the outside and facing an aquesous environment.

Usually provide the strutural foundatoin of CELL MEMBRANES
What is this general structure represent?
a steroid which is one of the groups of lipids.
How are steroids often characterized?
charatcterized by a backbone of four linked carbon rings.
What are examples of staroids?
certain hormones (ie. testosterone and estrogen)
WHat are the four classes of organic molecules?
1) carbohydrates
2) Lipids
3) Proteins
4) Nucleic Acids
What are the five main groupings of proteins, categorized according to their functions?
1) Strcutural Porteins
2) Storage Proteins
3) Transport Proteins
4) Defense Proteins
5) Enzymes
How are all groupings of proteins similar?
All proteins are polymers of amino acids, that is, they consist of a chain of amino acids covalently bonded.
What are the bonds between amino acids called? And what is a chain of them called?
peptide bonds
A chain of peptide bonds is a polypeptide or peptide.
How then do proteins differ from one another?
they differ by the number and arragnement of the twenty different amino acids.
What is an amino acid consist of?
central carbon bonded to an amino grop (-NH2), a carboxyl group (-COOH), and a hydrogen atom
What is this a strcutre of?
THe general structure of an amino acid
What are the four levels that describe a protein?
What does the primary structure of a protein mean?
describes the order of amino acids.
def secondary structure

What does the binding produce?
is a three-dimensional shape that results from hydrogen bonding between the amino and carboxyl groups of adjacent amino acids.

The bonding produces:
1) a spiral (Alpha Helix) or
2) Folded Plan (Beta Sheets
def tertiary structure
includes additional three-dimensional shapng and often dominates the structure of GLOBULAR PROTEINS.
What intermolecular forces contribute towards the tertiary structure?
- Hydrogen bonding between R groups of amino acids
- IONIC BONDING: between R groups of amino acids
- The HYDROPHOBIC EFFECT that occurs when hydrophobic R groups move toward the center of the protein = globular
- DISULFIDE BONDS are formed when the sulfur atom in the amino acid cysteine bonds to the sulfr atom in another cystein = DISULFIDE BRIDGE
define quaternary protein structure.

What inter molecular forces contribute to its stucture?

What is an example?
describes a protein that is assembled from two or more separate peptide chains.

Same forces that define the tertiary structure also effect the quaternary structure.

What is a nucleic acid?
THe term nucleic acid is the overall name for DNA and RNA. Nucleic acids where named for their initial discovery within the nucleus, and for the presence of phosphate groups.
Nucleus + Phosphate group =
Basic term for nucleic acid
Where is genetic information stored?
How is the genetic passed along?
deoxyribnucleic acids DNA

DNA passes its genetic information to ribonucleic acid (RNA) for directing various metabolic activities of the cell.
DNA is a polymer of what?
What are nucleic acids made of?
THey are lindear polymers (chains) of nucleotides?
What comprises a nucleotide?
1) Nitrogen base
2) Five-carbon sugar called deoxyribose
3) Phosphate group
WHat is this?
a nucleotide
Which nitrogen bases are bigger Pyrimidines or purines?
How can you remember Purines and Pyrimidines?
Pure Ag (Gold)

How doe purines and pyrimidines match up? And which one is stronger?
A-T (Double Bonded)
G-C (stronger b/c Triple Bond)
How do two strands of a DNA helix line up?
Both of the strands are oriented in opposite directions.

FIRST STRAND: 5' -> 3'
2ND STRAND : 3' -> 5'

They begin with phosphate group attached to the FIFTH (5') carbon of the deoxyrbose and ends where the phosphate of the next nucelotide would attached, at the THIRD (3') carbon of the deoxyribose.
1) The sugar in the nucleotides that make an RNA molecule is ribose, NOT deoxyribose as it is in DNA

2) Uracil pairs with adenine instead of Thymine

3) RNA is usually single-stranded and does not form a double helix as it does in DNA
Chemical reactions that occur in a biological system are ___

What does it include?
energy transfer
The breakdown of substances is called:

The formation of new products is
1) catabolism ("canables like to break down humans")

2) synthesis/anabolism
What are enzymes?
They are globular proteins that act as catalysts for metabolic reactions.
What are the characteristics of an enzyme?
1) The substrate is the substance or substances upon which the enzyme acts

2) Substrate specific
3) The induced-fit model describes how enzymes work
4) AN enzymes is UNCHANGED as a result of a rxn.
5) EFFICIENCY is effect by TEMPERATURE and pH.
Who is the substrate, amylase or amylose (starch)?
amylose/starch is the substrate, and the enzyme amylase breaks starch down.
T or F reactants are also termed substrates?
T or F, enzymes are proteins?
Is the active site on the enzyme or substrate?
The enzyme
What does the induced-fit model tell us?
How enzymes work:
Interaction of the reactants (substrate) and the enzyme causes the enzyme to change shape.

- THe new position places the substrate molecules into a position favorable to their reaction.

- ONce the rxn takes place, the product is released
What is the optimal temperature for enzymes?

At went temp. do enzymes find it unfavorable? what happens to them?
The temperature of the human body 98.6 F / 37.5 C

Unfavorable at 104 F, enzymes begin to DENATURE
What are cofactors?
They are non-protein molecules that assist enzymes.
What is a holoenzyme?

What is a apoenzyme
holoenzyme = apoenzyme + cofactor

apoenzyme = enzymes that require a cofactor but do not have one bound
What are coenzymes?

What is an example?
are organic cofactors that usually function to donate or accept some component of a rxn, often electrons.

Some vitamins are coenzymes or components of coenzymes
What are inorganic cofactors? give ex
they are often metal ions, like Fe^2+
The most common source of activation energy for metabolic reactions are
How does ATP supply energy to an rxn?
is usually energy in the last bond that is delivered to the reaction.
What happens to ATP in the process of giving up his energy?
THe last phosphate bond is broken and the ATP molecule is converted to ADP (adenosine diphospate) and a phosphate group (indicated by Pi)
How are new ATP molecules produced?
ATP molecules are assembled by PHOSPHORYLATION when ADP combines with a phosphate group using energy obtained from some energy-rich molecule like glucose.
What is ATP essentially?
it is an RNA adenine Nucelotide with two additional phosphate groups.
What happens in rxn 1 and 2?

1) ATP -> ADP + Pi

2) ADP + Pi -> ATP
1) ATP supplies energy to system

2) ATP is reformed through phosphorylation.
What are the four common general charactersitics of metabolism?
1) Equilibrium
2) Enzymes
3) Cofactors
4) ATP
What is regulated when enzymes are regulated?
chemical rxns and how to start or stop reactions are often regulated through enzymes
What are the four ways enzymes are regulated?
1) Allosteric Enzymes/feeback inhibition
2) competitive inhibition
3) noncompetitor inhibitor
4) Cooperativity
What are allosteric enzymes?
THey have two binding sites--one active site for the substrate and one allosteric site for an allosteric effector.
WHat is allostery?
changing the shape and activity of an enzyme that results from molecule binding with a regulatory substance at a site other than the enzymatically active one.
WHat is allosteric regulation?
is the regulation of an enzyme or the protein by binding an effector molecule at the protein's allosteric site (that is, a site other than the protein's active site)
T or false a protein has both active and allosteric sites (both are different sites)
What are the two binding sites for allosteric enzymes?
1) an active site for the substrate
2) one an allosteric site for an allosteric effector.
What is an effector?
An effector is a molecule that binds to a protein/enzyme and thereby alters the activity of that protein.
What are the two allosteric effectors and what do they do?
1) allosteric activator = binds to an enzyme and induces the enzyme's ACTIVE FORM.

AKA enhances the protein's activity.

2) ALLOSTERIC INHIBITOR binds to the enzyme and induces the enzyme's INACTIVE FORM.

or decreases the protein's acivity
An end product of a series of rxns acts as an allosteric inhibitor, shutting down one of the enzymes catalyzing the reaction series.
What is competitive inhibition?
a substance that mimics the substrate ingibits an enzyme by occuping the active site. The mimic displaces the substrate and prevents the enzyme from catalyzing the substrate.
What is non competitor inhibitor?
THis binds to an enzyme at locations other than an active or allosteric site. The inhibitor changes the shape of the enzyme which disables its enzymatic activity.
What are some important locations on an enzyme?
active sites and allosteric sites
What happens in cooperatively? WHat is an example.
an enzyme becomes more receptive to additional substrate molecules after one substrate molecule attaches to an active site.

"Let's cooperate and invite others to the party after the first shows up"

Example: Hemoglobin's binding capacity increases after the first oxygen binds to its binding site. Other oxygens are then invited to other sites.
1) Protein is a polymer of what?

2) Nucleic Acid is a polymer of what?

3) Starch is a polymer of what?
4) glycogen is a polymer of what?
5) cellulose is a polymer of what?
1) amino acids

2) nucleotides

3-5) all are made up of glucose monomers
What are the characteristics of hydrophilic properties?
1) polar molecules
2) molecules soluble in water
3) molecules that readily ionize in water
4) the hydroxyl group (OH)
What do plants convert into to make?
Plants use photosynthesis process and use CO2 and water to make carbohydrates
Maltose and sucrose are examples of what?
How are dissacharides made and what is lossed?
Dehydradtion (Condesation) synthesis and water is lost.
Glycogen and starch are examples of what?
Which of the following serves at the structural role in plants?

A. Glycogen
B. Amylose (Starch)
C. Cellulose
C. Cellulose
True of false, glycogen, starch and cellulose are all soluble in water?
Polymers are made through ->
Polymers are broken through ->
hydrolysis ( water + separation)
T or False Glycogen and glycerole are lipids

Glycogen is polysaccaharide carbohydrate

Gycerole is the backbone of lipids.
What are the five lipids derivatives?
1) Phospholipids
2) Waxes
3) Steroids
4) Carotenoids
5) Porphyrins
What include steroids?
sex hormones (testosterone and estrogen)
What are carotenoids and what are they a derivative of?

What are the two subgroups
Derivative of Lipids.

carotenoids are compounds that are the PIGMENTS which produce red, yellow, orange and brown colors in plants and animals.

1) carotenes
2) xanthophylls
What are cartoenes?

They come from:
Lipid -> carotenoids -> carotenes

THey are synthesized by PLANTS but cannot be made by ANIMALS.
What are xanthophylls?
Yellow pigment

THey come from:

Lipids -> Carotenoids -> xanthophylls

Contain oxygen atoms
WHat is the main difference between carotenes and xanthopylls?
Carotenes = orange color, purely hydrocarbons with no oxygen

xanthophylls: yellow pigment, contain oxygen atoms
Proteins can be classified on the bases of structure. There are classes of protein structure. List them all.
1) simple proteins =
2) albumins and globulins
3) scleroproteins
4) conjugated proteins
5) lipoproteins
6) mucoproteins
7) chromoproteins
8) metalloproteinss
9) nucleoproteins.
simple proteins are
composed entirely of amino acids
albumins and globulins are
proteins primarily globular in nature. They are the functional proteins that act as carriers or enzymes.
scleroproteins are....

what is an example
these are fibrous in nature and act as structural proteins. Collage is a scleroprotein.
conjugated proteins are ...
these contain a simple protein portion, plus at least one nonprotein fraction.
llipoproteins are...
protein bound to a LIPID
mucoproteins are...
protein bound to CARBO.
chromoproteins are...
protein bound to pigmented molecules
metalloproteins ...
protein complexed around a METAL IONS
nuceloproteins are...
protein containing histone or protamine (nuclear protein) bound to NUCLEIC ACIDS
What are the 5 general functions of proteins?
1) Hormones
2) Enzymes
3) Structural proteins
4) Transport proteins
5) Antibodies
What are hormones?/
They are proteins that function as chemical messnger
What is an example of a transport protein?
WHat is an example of a structural protein both extra and intra cellular?
extracellular: collagen in cartilage, bone and tendons

intracelullar: proteins in cell membranes.
Antibodies are what?
They are proteins that bind to foreign particles (antigens), including disease-causing organisms, that have entered the body.
Antigens are what?
foreign particles that entered the body.
Are all of the following about enzymes true?

1) Lower activation energy of a rxn
2) increase the rate of rxn
3) Do not effect the overall Delta G of the rxn
4) Are not changed or consumed in the course of the rxn
True or false most enzymes are reversible?
What factors effect the enzyme action and the reaction rate depend on?
Concentration of Enzyme
Concentration of Substrate
At what pH do enzymes work best? What are some exceptions?
Work best at pH 7.2

Pepsin works in stomach at highly acidic conditions (pH=2)

Pancreatic enzymes works in small intestine (pH=8.5)
True or false: Every reaction in the body is regulated by enzymes
What enzyme hydrolyzes lactose to the monosaccharides glucose and galactose?

A. lactase
B. proteases
c. lipases
What enzyme degrade proteins to amino acids?

a. lactase
b. protease
c. lipase
what enzyme hydrolyzes (break down) lipids to fatty acids and glycerol?

a. lactase
b. protease
c. lipase
True or false: Synthesis (dehydration) reactions can be catalyzed by the same enzymes as hydrolysis reactions, but the direction of the reaction is reversed.
What are prosthetic groups?
cofactors which bind to the enzyme by strong covalent bonds
What are cofactors?
a nonprotein molecule that incorporate themselves on a enzyme so that they become active.
WHat are the sub units nucleic acids?
Nuncleic acids are polymers of what?
What are the four points to The Cell Theory?
1) All living things are composed of cells
2) THe cell is the basic functional unit of life
3) Cells arise only from pre-existing cels
4) Cells carry genetic information in the form of DNA. THis genetic material is passed from parent cell to daughter cell.
What are the three microscopy techniques for studying cells? is the organism alive or dead?
1) Compound Light Scope (cell is dead). Total magnification
2) Phase contrast microscopy (specimen is alive).
3) electron microscopy (specimen is dead). thousand fold magnification.
What are the differences between prokaryotes and eukaryotes in cell biology? First give an example of both, as a reference point to compare.

Compare the:
Cell Wall
Membrane bound organelles
Prokaryotes: Bacteria
Eukaryotes: Protists, fungi, plants, animals

Cell Wall:
-PROK = Yes;
- EUK =No, protists, animals Yes: fungi and plants

-PROK: No All
-EUK: Yes All

-PROK: subunits = 30S and 50S
-EUK: subunits = 40S and 60S

Membrane bound Organelles
-PRO = No all
-EUK = Yes all
The fluid matrix in inside the cel is called?
What two things can move freely about the lipid bilayer/plasma membrane?
lipids and most proteins
What are the three common proteins found in the phospholipid bi layer?
peripheral proteins
integral proteins
transmembrane proteins
Proteins may attach loosely to the inner or outer surface of the membrane are called:

peripheral proteins
integral proteins
transmembrane proteins
peripheral proteins
Proteins that extend into the membrane are called:

peripheral proteins
integral proteins
transmembrane proteins
integral proteins
Integral proteins that span across the membrane, appearing at both surfaces are called:

peripheral proteins
integral proteins
transmembrane proteins
transmembrane proteins
proteins that extend out of the surface are called

peripheral proteins
integral proteins
transmembrane proteins
peripheral proteins
T or F. both peripheral and integral proteins are amphipathic?
False only integral proteins.
The nature of scattered proteins within a flexible matrix of phospholipid molecules describes the ...
fluid mosaic model
What molecules can freely pass through the phospholipid membrane?
only small,
- polar molecules (ie H20 and CO2)
- hydrophobic molecules (nonpolar molecules like O2)
What molecules can NOT freely pass through the membrane?
Large polar molecules (ie glucose)
- All ions are impermeable
What do carrier proteins do?
They assist some larger charged molecules across the membrane
What are the top 6 functions proteins play in the membrane?
1) Channel proteins
2) Transport Proteins
3) Recognition Proteins
4) Adhesion Proteins
5) Receptor proteins
6) electron transfer proteins
Channel proteins do what?
provide passageways through the membrane for certain hydrophilic (water-soluble) substances such as polar and charged molecules.
Transport Proteins do what?
spend energy (ATP) to transfer materials across the membrane. When energy is used for this purpose, the materials are siad to be actively trasnported, adn the process is called active transport.
What do Recognition proteins do?
distingish the identify of neighboring cells. These proteins are called GLYCOPROTEINS b/c they have short polysaccharide chains (oligosaccharides) attached. The ologosaccharides part of the glycoprotein protrudes from the surfacd of the membrane like an entenna.
What to Adhesion proteins do?
Attach cells to neighboring cells or provide anchors for the internal filaments and tubules tha give stability to the cell
What do receptor proteins do?
provide binding sites for hormones or other trigger molecules. IN response to the hormone or trigger molecule, a specific ell response is activated.
What do electron transfer proteins do?
are involved in transferring electrons from one molecule to another during chemical reactions.
What do cholesterol molecules do in the phospholipid bilayer?
they provie some rigidity to the plasma membranes of animal cells.

In plant cells, related substances (sterols) provide a similar function.
What is glycocalyx and what does it do?
It is a carbohydrate "coat" coverign the outer face of the plasma membrane. It consists of various oligosaccharides that are attached to membrane phospholipids (glycolipids) and proteins (glycoproteins or recognition proteins). THe glycocalyx provides makers for cell-cell recognition.
What are the the three things that comprise the nucleus?
Nuclear envelope (similar to the phospholipid bilayer)
- nucleolus
- chromatin
What does the nucleus contain?
When a cell is not replicating what is DNA like?
DNA is spred out in a threadlike matrix called CHROMATIN
When a cell is about to divide DNA in the form of _____begins to condense into _______.
chromatin, chromosomes
What are chromosomes made up of?
- Two long DNA molecules
- various histone (protein) molecules
What are the purpose of histones in DNA?
They serve to organize the lengthy DNA, coiling it into bundles called nucleosomes.
WHat is the nucleolus?
is a dense structure in the nucleus where ribosomal RNA (rRNA) synthesis occurs.
Where in the cell is the site for separation?
The nucleus
What are ribosomes?

What is there function in the cytoplasm?
Ribosomes subunits are manufactured in the nucleolus and consist of RNA molecules and proteins.

In the cytoplasm ribosomes assist in the assembly of amino acids into proteins.
Where are free ribosomes and bound ribosomes found?
free ribosomes = in cytoplams
bound ribo...= line the outer membrane of the endoplasmic reticulum
What is the Rough Endoplasmic Reticulum (ER) and what is it's main function?
is a network of membrane-enclosed spaces

Function: involved in the transport of materials throughout the cell...PARTICULARLY those materials destined to be secreted by the cell.
What is the ER rough?
It is surround by ribosomes.
WHat makes proteins?
Who else helps with protein synthesis?
The Rough ER
Smooth ER is repsonspsible for what? What is it responsbile for in the liver?
the synthesis of lipids and hormones, especially in cells that produce these substances for export from the cell.

IN the liver the smooth ER is invovled for breakdown of toxins, drugs and toxic by-products from cellular reactions.
What is the golgi apparatus responssible for?
They function to modify and package proteins and lipids into VESICLES, small, spherically shaped sacs that bud from the outside surface of the Golgi apparatus.
THe KKB relates the Golgi apparatus like UPS. WHat for?
Well Like UPS the golgi apparatus receives vesicles and their contents from the smooth ER, modifies them, repackage them into vesicles, and distributes them to the cell surface for exocytosis.
What are lysosomes and where to they originate from?
The come from a Golgi apparatus that contain digestive enzymes
What are peroxisomes?
They are organelles that break down various substances. O2 combines with hydrogen to from toxic hydrogen peroxide, which in turn is converetd to H2O

THere are commonly found in the liver and kindeys and in photosynthesizing plant cells
Where does the majority of the cells metabolic activity occur?
THe cytoplasm
What is the function of Chloroplasts?
They carry out photosynthesis, the plant process of incorporating energy from sunlight into carbohydrates.
What is the function of microtubules?
THey are made of the protein tubulin and provide support and motility for cellular activities.

They are found in the spindle apparatus.
What does the spindle apparatus do?
guides the movement of chromosomes during cel division.
Intermediate filaments provide support for what?
maintaining the shape of the cell
Microfilaments are made of what and involved in what?
Made of actin and is involved in cell motility, mechanical support, maintains cell shape.
What are centrioles?
They are specialized microbule involved in spindle organization during cell division and are not bound by a membrane.

The region where they lie is CENTROSOMES
How are Plant Cells Distinguished from Plant Cells?
1) Presence of cell walls, chloroplasts, an central vacuoles IN PLANTS. NOT IN ANIMALS

2) presence of lysosomes and centrioles IN ANIMALS. NOT IN PLANTS
the net movement of dissolved particles down their concentration gradients

High Conce -> Low Conc.

Passive Process
Is simple diffusion of water from a region of:

Lower Solute Conc. -> Higher Solute Conc.
Water likes to move where during osmosis
It likes going to more conentrated areas
When the cytoplasm of a cell has a lower concentration than the extracellular medium what will happen?
The cell is in Hypertonic solution.

Water will flow out of the cell to the more concetrated medium.

THis is called pasmolysis
If the extracellular environment is less concentrated than the cytoplasm of the cell , the extracellular medium is said to be ______ and what will happen?
hypotonic, the cell will burst (lyse)
What are the three main types of transport?
Passive diffusion:
- Down Gradient
- NO carrier
- No energy required

Faciliated Diffusion:
- Down Gradient
- Carrier
- No energy required

Active Transport:
- Against gradient
- carrier
- energy required
WHat types of things are transported during active transport?
small ions (Na+, K+, Cl-, H+)
amino acids

...across the membranes
How are things circulated in the cell (Intracellular circulation)?
1) Brownian Movement
2) Cyclosis or streaming
3) Endoplasmic reticulum
What is Brownian Movement?
the movement of particles due to kinetic energy which spreads small suspended particles throughout the cytoplasm of the cell
What is cyclosis or streaming?
the circular motion of cytopasm around the cell trasnport molecules
How is the movement of materials on a large, extracellular circulation, done through the body of an organism?
1) Diffusion: If organisms cells close to the external environment. i.e transprot for food and oxygen from external environment. ANd even transport of materials between cells and interstitiaul fluid which batehs the cells

2) Circulatory System: If organisms cells are not close to external environment. vessels are used to move things around if the cells are too far from the external environment.
How do prokaryotes and eukaryotes differ in their organization of genetic material?
Prokaryotes: genetic material is composed of a single circular molecule of DNA localized in a region of the cell called the nucleoid.

Eukaryotes: have highly coiled linear strands of DNA organized into chromosomes within a membrane-bound nucleus.
How do prokaryotes and eukaryotes differ in their site of cellular respiration?
Prokaryotes: cellular resp. occurs directly at the cell membrane.

Eukaryotes: celular resp. occurs across the mitochondrial membrane and within the mitochondria itself.
How do prokaryotes and eukaryotes differ in their presence of membrane-bound organelles?
Prokaryotes: don't have them

Eukaryotes: Have them
What are the only Prokaryotes?
What kingdoms are the eukaryotes?
Protists, Fungi, Plants, Animals
Movement of solutes across a plams membrane from a region of igher solute conc. to a region of lower solute conc. with the aid of proteins is...
Facilitated diffusion
Movement of water across a membrane from a region of higher concentration to lower conc. of water is....
Movement of water out of a cell resulting in the colllapse of the plasma membrane
Movement of urine through the urinary tract
bulk flow
Movement of solutes across a plasma membrane requiring the addition of energy...
active transport
Karyokinesis is ____________
Cytokinesis is _____________

Which comes first?
1) nuclear division
2) cell division

Nuclear division comes first in Motisis
Where does a cell spend most of its life?
What happens during Interphase?
Each chromosome is replicated so that during division , a complete copy of the genome can be distributed to both daughter cells.
Before replication what does the genetic material look like and what is its name?
What is the difference between Chromatin and Chromatids?
Chromatin: DNA Uncoiled.

Chromatid: DNA Coiled
How many chromatids equal a chromosome?

Where do the two chromatids join at?
two Chromatids = 1 Chromosome

What are the four phases in Mitosis?
What three activities happen in Prophase?
First: the nucleoli disappear and the chromatin condenses into chromosomes ( or also termed single chromatid.
True or False: Each Chromatid is composed of a complete, double-stranded molecule of DNA.
True or False the term "chromosome" may be used to refer to either the single chromatid OR the pair of chromatids attached at the centromere.
What 3 steps happen in Prophase?
First: THe nucleoli deisappear and the chromatin condenses into chromosomes.

Second: the nuclear envelope breaks down.

Third: The mitotic spindle is assembled
How does the mitotic spindle begin to develop?
Centromeres begin moving at opposite ends.
- As they move microtubules develope increasing in length by the addition of tubulin.
- Once on each side of the nucleus the microtubules connect to a specialiezed region on the centromere called the KINETOCHORE.
-Microtubules an begin tugging, moving the chromosomes back and forth.

Now we enter metaphase.
How many centrioles are at the centrosome? Are they located outside or inside the cell?
2 Centrioles per centrosome (kind of like the h-"ome" of centrioles.
What key feature is characteristic of Interphase?
The centrioles are still at the centrosome...waiting to be put in position.
microtubules are made from ___
microfilaments are made from____
micro-"tubules" = Tubulin
microfil-"A"-ments = A-ctin
What roles do the microtubules and microfilaments do?
microtubules: guides movement of chromosomes in cell division

microfilaments = when the shorten they act as a purse string to pull the plasma membrane into the center, dividing the cell into two daughter cells. The groove created by these purse strings is called CLEAVAGE FURROW.
When does metaphase begin? Continue the process of what happens.
Begins when chromosomes are distributed across the metaphase plate.

Ends when microtubules begin pulling the chromatids apart

Entering Anaphase
T or False, once a chromosome is pulled apart, the chromatid that is separated from its sister is now called a chromosome?
What happens in Anaphase?

Begins: after the chromosomes are separated into chromatids. The microtubules connected tot he chromatids (now chromosomes) shorten, pulling the chromosomes to opposite pulls.

End: at the end of this phase each pole has a complete set of chromosomes, the same number of chromosomes as the original cell.
True or false: Since a cell consists of only one chromatid, each chromosome contains only a single copy of the DNA molecule after cell division
What happens in telophase?
- Nuclear envelope develops, forming two nuclei
- Chromosomes (aka chromatid) disperse into chromatin (uncoiled DNA), and the nucleoli reappear.

Simultaniously Cytokenisis occurs, dividing the cytoplasm into two cells.
What causes cleavage furrow during cytokinesis?
the microfilaments, aka purse strings.
What are the two major differences between cell division in animal cells and plant cells?
1) Plants lack centrioles
2) Cytokinesis:
- in animal cells (CLEAVAGE FURROW) proceeds through production of Cleavage Furrow.

-In Plant cells (CELLS WALLS) can't cleavage furrow. Vesicles originating from Golgi bodies migrate to the plane between two newly forming nuclei. The vesicles fuse to form a cell plate = turns into plasma membranes for the two daughter cells
TRUE OR FALSE: During interphase growth occurs in all three phases of G1, S, and G2
At which phase in Interphase marke the time during which teh second DNA molecule for each chromosome is synthesized?
the S phase
TDNA is replicated during what phase?

What is the result of DNA replication?
Each chromosome that appears at the beginning of the next mitotic division will appear as two sister chromatids.
During what period of growth are materials for the next mitotic division are prepared?
True are fallse. Centrosomes also replicate?
Where do centrosomes replicate?
During Interphse (S)
T or F: Microtubules only attach to the chromosomes during prophase?
False. Microtubules are also attach to places around the cell to help pull things apart.
For all organisms, what does haploid and diploid mean.
Haploid = N = half the number of total chromosomes

Diploid = 2N = Full number of chromosomes.
What types of cell go through meiosis?
germ cells
When two homologous chromosomes come together and intertwine this is called
What does homologous chromosomes mean?
chromosomes that code for the same traits, one inherited from each parent
What is crossing over and where does it occur?
Crossing over occurs between chromatids of homologous chromosomes and break at correspond ponts and exchange equivalent pices of DNA, one from the father and mother.

Note: crossing over cannot happen between sister chromoatids. It would be like exchanging information with yourself. That is why only homologous chromosomes can do it because they are from two different people.

Occurs at Prophase I of Meiosis
What is a tetrad?/
During Prophase I of meiosis each synaptic pair of homologous chromosomes contain four chromatids
T or False. once crossing over occurs sister chromatids are no longer identical
What happens in Metaphase I in meiosis?
Homolgous pairs (Tetrads) algin at the equatorial plate
- each pair attaches to a seperate spindle fiber by its kinetochore.
What happens in Anaphase I of meiosis? And what is the process generally called in terms of genetics?
- Homologous pairs (tetrads) are pulled to opposite poles
T OR F: The Meiosis I is exactly like Mitosis?
False: Meiosis two is exactly like Mitosis.
What is the one difference between Meiosis II and Mitosis?
Mitosis: Chromosomes replicate
Meiosis II: Chromosomal replication does NOT occur, which is why each new cell ends up with a haploid number of chromosomes.
Mitosis In Nutshell True or False:

2N -> 2N
- Occurs in all dividing cells
- Homologous chromosomes do NOT pair up
- Crossing over occurs
False: Everything is true but crossing over. It does not occur in mitosis. Sister chromatids cannot cross over = no genetic variation
Meiosis in a nutshell True or False:

- 2N -> 2N
- Occurs in sex cells only
- Homologous chromosomes pair up at metaphase plate forming tetrads
- Crossing Over can occur
False: It goes from 2N -> N
What are the different types of asexual reproduction:
What type of reproduction to Prokaryotes

Prokaryotes: ALL asexually
Animals: Most sexually, Asexual reproduction is more prevalent among invertebrates
Plants: All, both simple and complex, use sexual repro.
If a cell has 46 chromosomes at the beginning of mitosis, then at anaphase there would be a total of...

23 chromatids
23 chromosomes
46 chromosomes
46 chromatids
92 chromosomes
E. 92 Chromosomes
If a cell has 46 chromosomes at the begginning of meiosis, then anaphase I there would be a total of...

23 chromatids
23 chromosomes
46 chromosomes
46 chromatids
92 chromosomes
46 chromosomes
True or false: All eukaryotic cells have centrioles?
False, Most plants do not have centrioles
What is fission?
Who normally goes through it?
What: The DNA replicates and a new plasma membrane and cell wall grow inward along the midline of the cell,
-dividing it into two equally-sized cells with
- equal amounts of cytoplasm, - each containing a duplicate of the parent chromosome.

Who: Prokaryotes, one-celled organisms such as amoebae, paramecia, algae, bacteria
What is Budding?
Who usually goes through it?
What: the repication of nucleus followed by UNEQUAL cytokinesis.
- smaller than parent
- genetically identical
- grows to adult size

Who: Hydra and yeast
What is regeneration?
WHo usually goes through it?
What: is the growth of a lost or injured body part and occurs by mitosis.

Who: Lower animals like hydra and starfish
- Salamanders and tadpoles
What is Parthanogenesis?
Who usually goes through it?
What: is the development of an unfertilized egg into an adult organism.

Who: Bees and Ants
Male Bees = unfertilized eggs
Worker and Queen bees = fertilized eggs
What does meiosis produce in plants?
What are spores?
Spores are haploid cells that divide by mitosis to become a multicellular haploid structure, the gametophyte.
Know that plants have different phases in their life. Sporophyte and gametophyte generations/phases
In plants what phase of their life do they asexually reproduce?
sporophyte generation: when they are a plant having roots etc.
What is alternation of generations?
which a diploid generation is succeeded by a haploid generation.
Is the sporophyte generation diploid or haploid?

Which generation produces haploid spores?

What do spores go through _____to produce _______.
mitosis, gametophytes
What two ways to plants asexually reproduce?
1. Spore formation
2. Vegetative propigation
What are the two types of vegetative propagation?
1) Natural Vegetative Prop
2) Artificial Vege..
WHat is vegetative propagation?
undifferentiated tissues in plants, called meristems, provide a source of cells that can develop into an adult plant.

= no genetic variation
- rapid reproduction
Certain types of plants can each go through natural propagation. And each have special propagation parts. What are those parts and give examples of each.
Bulbs: Tulips and Daffodils
Tubers: Potato
Runners: Strawberries and lawn grasses
Rhizomes (stolons): ferns and iris plants
Define each of these:
bulbs: split into form several bulbs
Tubers: underground stems with buds, like the eyes of potatoes, that can develop into adult plants
Runners: are stems running above and along the ground, extending from the main stem
Rhizomes: are woody, underground systems. THey can develop new upgright stems as they do in ferns and iris plants
WHat is artificial propagation?
Humans way of making plants reproduce asexually.
What are the male and female gonads called? What do they prod?
Testes produce sperm and ovaries produce oocytes (eggs)
What is the term for an organism that has both male and female gonads?

give examples

Hydra and earthworm
What is the production of gametes for both male and female?
What are the cells called in spermatogenesis?
Diploid or haploid
goes through meiosis or mitosis
produce 4 or two sperm of equal size
called spermatogonia
- diploid cells
- go through meisosis
- 4 haploid sperm of equal size are produuced
THe head of the sperm consists of what?
The tail is what?
Head consists almsot entirely of the nucleus which contains the paternal genome
- tail is flagellum
During oogenesis the female sex sell goes through what?
How many cells go through this?
Is it a diploid or haploid cell?
What does this process produce and how much does it produce?
1) goes through meiosis
2) Only 1 sex cell
3) Diploid
4) produces a single mature egg/ ovum
Each meiotic division during oogenesis produces what?
A polar body which is a small cell that contains little more than the nucleus.
What does the mature ovum contain?
cytoplasm, RNA, organelles, and nutrients
What are the two types of fertilization?
External and Internal
External: Fish and amphibians, sperm have flagellum, female produces a crap load of eggs to increase chances of fertilization

Internal Fertilization: Species that care for their young produce fewer eggs
Besides sperm what else is produced in the testes? What does it regulate?
the male hormone TESTOSTERONE. It regulates secondary male sex characteristics including facial and pubic hair and voice changes
1) Where are the ovaries located?
2) Ovareis consists of thousands of what?
1) The abdominal cavity, below the digestive system
2) follicles = a multi-layered sac of cells that contains, nourishes, and protects an immature ovum.
What cells produce estrogen and where are these cells found?
Ovaries -> follicle -> follicle cells -> estrogen
Describe the path that an immature ovum takes each month.
ovum (egg) -> released from the ovary into the abdominal cavity -> drawn to oviduct -> uterus
This location is the site of fetal development:
A. fallopian tube
B. oviduct
C. uterus
D. Cervix
C. Uterus
where are the female sex hormones produced?
What are they?
How are they regulated?
Ovaries produce estrogens and progesterone -> secretion is regulated by LH an FSH -> which is regulated by GnRH
From the top down how are the two female sex hormones regulated
1) GnRH regulates
2) LH and FSH who regulate
3) estrogen and progesterone
What are estrogens?
What do they do/responsible for?
Who secretes them
They are steroid hormones necessary for normal female maturation
- stimulate the development of the female reproductive tract
- contribute to secondary sexual characterstics
- stimulate sex drive
- responsible for thickening of the endometrium (uterine wall)

Secreted by:
ovarian follicles and corpus luteum
What is progesterone?
What does it do?
Who secretes it?
Progesterone is a steroid hormone
Function: stimulates the development and maintenance of the endometrial walls in preparation for implantation.

Secreted by:
Curpus leteum during the luteal phase of the menstrual cycle
How is the menstrual cycle split up?
1) follicular phase
2) luteal phase
3) menstruation
What are the three sites of hormonal secretions that play a role in the female reproductive cycle?
anterior pituitary
What happens in the follicular phase? What phase happens next?
Anterior Pituitary Hormone releases -> FSH -> Follicle starts to grow -> follicle cells secrete -> estrogen ->Enter ovulation phase
What happens during the ovulation phase?
WHat causes it?

What happens next?
a mature ovarian follicle bursts ->releases an ovum

Caused: ovulation is caused by a surge in LH which is preceded, and in part caused, by a peak in estrogen levels

Luteal phase happens next
What happens in the Luteal phase?

What happens next
LH induces the ruptured follicle to develop into -> corpus luteum, wich secretes -> estrogen and progesterone.

Progesterone causes the glans of the endometrium to mature and produce secretions that prepare it for the implantation of the embryo. Progesterone and estrogen are essential for the maintenance of the endometrium

NExt phase is Menstruation
What happens during menstruation if:
1) Not fertilized
2) Fertilized
1) If the ovum is not fertilzed, the corpus leteum atrophies -> estrogen and progesterone levels drop -> endometrium lining sluffs off (blood) -> menstrual flow (menses)

2) If fertilization occurs -> the developing placenta produces hCG (guman chorionic gonadotropin) -> maintain corpus luteum -> thus, supply of estrogen and progesterone maintains uterus -> until placenta takes over production of these hormones
In plants what has evolution leaned towards the dominant generation?
diploid sporophyte generation
How does the gametophyte generation produce gametes?
through mitosis
How is the sporophyte generation restord?
by union of the male and female gametes at fertilization, restores the diploid sporophyte generation
Which plant generation reproduces sexually and asexually?
Gametophyte sexually (b/c they restore diploid sporophyte gen)

Sporophyte asexaully (b/c they restore haploid gametophyte generation)
Which generation is dominant in :
Mosses: gametophyte is dom
Ferns: Sporophyte is dom
Angiosperms: Sporophyte gen is dominant
If you see a woody plant (maple, rose etc) what stage is it in?
sporophyte stage
What is the reproductive structure for angiosperms?
What is the male organ of the flower and what is the female organ?
Stamen = male organ
Pistil = female organ
What is the stamen an what does it consists of? And what does the anther produce
The male reproductive organ of the flower. Consists of thin stalk-like FILAMENT with a terminal sac called the ANTHER.

The anther produces haploid spores which develop into pollen grains
What is the pistil and what does it consist of? What do each of the three parts do?
Pistil = female organ of the flower.

Three parts:
1) Stigma - sticky and catches pollen
2) style = a tube-like structure connecting the stigma to the ovary at the base of the pistil
3) ovary- enlarged base of the pistil, containing one or more ovules.
What are sepals?
What covers the flower
In flowers what are the male and female gametophytes?
Males: pollen grain
Females: embryo sac containing nuclei including the two polar (endosperms) nuclei and an egg nucleus
In flowers when does fertilization occur? What happens? And what happens to the other sperm that enters?
occurs when the sperm nuclei enter the embryo sac.

One haploid sperm nucleus fuses with the haploid egg nucleus to form the diploid zygote, which develops into the embryo.

THe other sperm nuclues fuses with the 2 polar bodies to form the endosperm (triploid or 3N)
What N is the endosperm and what is its purpose? WHat happens to the sperm in dicotyledonous plants?
1 sperm nucleus + 2 polar bodies = 3N endosperm

Endosperm serves as food for the embryonic plant.

In dicotyledonous plants the endosperm is absorbed by the seed leaves (cotyledons)
In plant reproduction how does the zygote divide?
What does a plant embryo consist of?
1) Epicotyl
2) Cotyledons
3) Hypocotyl
4) Endosperm
5) seed coat
Epicotyl is..
the precursor of the upper stem and leaves
cotyledons is...
these are the seed leaves. Dicots have two seed leaves while monocots have only one.
hypocotyl. is...
this develops into the lower stem and root
Endosperm is...
the endosperm frows and feed the embryo. in dicots, the cotyledon absorbs the endopserm
seed coat is...
develops from the outer covering of the ovule.
embryo + seed coat = ?
the seed
What are meristem cells?
They are key embryonic cells in higher plant development. THese tissues undergo active cell reproduction Gradually, the cells elongate and differentiate into cell types characteristic of the species.
What are apical meristems and where are they found?

What are lateral meristems and where are they found?
found in the tips of roots and stems. Growth in length occurs only at these points

Lateral meristems or cambium is located between the xylem and phloem. This tissue permits growth in diameter and can differentiate into new xylem and phloem cells.
True or false: lateral meristem cells is not an active tissue in monocots (grasses) or herbaceous dicots (alfalfa) but is predominant in woody dicots like oaks?
What are the two main difference in mitosis between plants and animals
1) plants don't have centrioles
2) Plants develop cell wall, animals have cleavage furrow and divide by cytokinesis
The chromosome number of offspring produced via parthenogenesis is
A: diploid
B: haploid
C: 2N
D: Both A and C
B haploid
Genes are composed of what and located where?
composed of DNA and located on chromosomes
When a gene exists in more than one form, the alternative forms are called?
The genetic makeup of and individual is...

The physical manifestation of the genetic makeup is the individual's

WHat probability tech. is usually used when looking at genetics problems?
the multiplication rule
WHat does a gene represent?

In pea plants, there is a _____that _______for purple flowers.
it represents the genetic material on a chromosome that contains the instructions for creating particular trait.

gene that codes for purple flowers
A _____is one of several varieties of a gene.

In pean plants, there a retwo alleles of the gene for flower color-purple allele, which codes for purple flower, and the white allele, which codes for white flowers.
THe ____refers to the location on a chromosome where a gene is located.
If the two alleles inherited for a gene are different, one allele may be _____________, while the other is ______________.
dominant or recessive
What does homozygous dominant refer to ?
2) homozygous recessive
3) Heterozygous
refers tot he inhertiance of two dominant alleles (PP)
2) two recessive alleles are inherited (pp) and the recessive trait is expressed.
3) heterozygous refers to the condition where the two inherited alleles are different (Pp). The dominant allele is expressed
What does the law of segregation refer to?
During meiosis I homologous chromosomes migrate to opposite poles. As result, each gamete will contain one allele for each gene
In Mendel's experiment he mated or ______, two varieties of pea plant to form offspring, or ______
crossed, hybrids
A cross between a purple-flowerd pea and a white-flowered pea is called a _______. Why?
monohybrid cross, because it involves a gene for only on trait, the gene for flower color.
What do these mean:
1) P generation
2) F1 generation
3) F2 gen
P gen = the parents
2) F1 gen = the offspring from the crossing of the parents
3) F2 gen = the offspring produced from crosses among the F1

(F stands for filial, which refers to sons or daughters)
WHat is the only type of phenotype can the genotype be predicted with 100% accuracy?
ONLY a recessive phenotype
How would you determine the genotype of something?
do a test cross:
What is a test cross?

What genotype will you always know?
It is the mating of an individual whose genotype you are trying to determine with an individual whose genotype is unkown.

the recessive trait (pp)
What is the trend for Mendel's second law of independent assortment?
Two traits are being observed
- Both parents are homozygous
- Tall is dominant to dwarf and Purple is dominant to white
- Parents TTPP and ttpp.
- F1 = TtPp
- TtPp crossed with TtPp = 9:3:3:1
What is the phenotype of these crosses:

1) YYRR x yyrr
2) YyRr x YyRr
1) Only one phenotype: YyRr
2) Phenotype ratio: 9:3:3:1
What test is used to know if it is incomplete dominance?
Snapdragon: red flowers is R; white flowers is r. Combined Rr = pink.

or straight and curly hair crossed might yield wavy hair
What is codominance?
An inheritance pattern where both inherited alleles are completely expressed.
How will imagining a continuum help keep distinguish between the three kinds of inheritance?
One extreme = complete dominance by a dominant allele over a recessive allele.

Other extreme: Both allelels are expressed (codominance)

In the middle: a blending of two different alleles produces an intermediate phenotype (Incomplete dominance)
What is a classic example of codominance and multiple alleles?
ABO blood groups
If an individual with I^BI^B, I^Bi, or ii blood is given to type A blood, then the immune system of the recipient will identify the A Carbohydrate on the introduced red blood cells as a __________
foreign substance
What does the immune system term foreign substances and how do they respond to them?

What is the result?
THe immune system responds to foreign substances as ANTIGENS.

The immune system responds to antigens by producing ANTIBODIES that attack the antigens.

The result is clumping, or AGGLUTINATION, of the blood and possibly death.
What blood type is known as the universal donor?

the universal recipient?
Universal donor = O (b/c no A or B carbohydrates)

Universal recipient = AB (b/c has both A and B carbo = "self")
What is epistasis? Where does the frequently occur?
occurs when one gene affects the phenotypic expression of a second gene.
- This frequently occurs in the expression of pigmentation. One gene turns on (or off) the production of pigment, while a second gene controls either the amounf o pigment produced or the color of the peigment. If the first gene codes for no pigment, then the expression of the second gene has no affect, regardless of the kind of pigmentation it encodes.
This occurs in the pigmentation of fur in mice

A. Multiple Alleles
B. Pleiotropy
C. Polygenic Inheritance
D. Epistasis
D. Epistasis

One gene codes for the presence or absence of pigmentation. A SECOND gene codes for the color of pigmentation, black or brown. Thus, C and c represent the alleles for the presence and absence of color, and B and b represent the alleles for black and brown pigments. As the allele notation indicates, both genes are expressed by CCBB, CCBb, CcBB, and CcBb are all black, and the expressions of CCbb and Ccbb are both brown. However, whenever cc is inherited, no pigment is produced and the fur is white regardless of the color encoded by the B allele.
WHat is pleiotropy? What is an example?
Pleiotropy occurs when a single gene has more than one phenotypic expression.

I.e. one gene in pea plants can express not only for round or wrinkled but the same gene also influences the phenotypic expressions of starch metabolism and water absorption
What disease-causing gens exhibit pleiotropy?
sickle-cell anemia, a human blood disease, is caused by an allele that incorrectly codes for hemoglobin.
What is an example of polygenic inheritance what is it?
Def: the interaction of many genes to shape a single phenotype.

The heights of humans is an example. They are not just short or tall but are displayed as a CONTINUOUS VARIATION from very short to very tall. Continuous variation usually results from polygenic inheritance.
What is the difference between pleiotropy and polygenic inheritance?
Polygenic inheritance = many genes shaping one phenotype.


Pleiotropy = one gene influencing many phenotypes
What are linked genes?
Genes that reside ont he SAME chromosome and thus cannot segregate independently because they are physically connected. Genes that are linked are usually inherited together.
What is sex-linkage?
In humans, females have two W chromosomes, and males have only one. As a result, recessive genes tha are carried on the X chromosome will produce the recessive phenotypes whenever they occur in males, since no dominant allele is present to mask them. The recessive phenotype will thus be much more frequently found in males.
Describe how Hemophilia is a sex linked trait
Females and males who inherit the normal allele (H) are X^HX^H and X^HY = normal.

For a female to have hemophilia the offspring must be X^hX^h. The offspring must inherit both recessive X^h genes from each parent.

Males on only need to inherit one X^h recessive allele for them to have hemophilia: X^hY. Therefore hemophilia is more likely to occur in males.
What organism is often used to study genetics and why?
the Fruit Fly (Drosophila melangaster)

1: it reproducs often (short life cycle)
2: It reproduces in large numbers (large sample size)
3: Its chromosomes (especially in salivary gland) are large and easily recognizable in size and shape
4: Its chromosomes are few (4 pairs, 2n=8)
5: Mutations occur relatively frequently
True or false the Environement can affect the expression of a gene?

Give examples
Drosophila: witha given set of genes have cooked wings at low temperature, but straight wings at higher temperature

Himalayan Hare: Warm parts = white hair. Cold parts on body = black hair
What is x-inactivation? What is an example?
during embryonic development in female mammals, one of the two X chromosomes in each cell does not uncoil into chromatin.

Example is the Calico Cat
What is nondisjunction? What are two genetic defects as a cause from this?
The chromosomes, during meiosis, do not properly separate.

Down Syndrome and Turner Syndrome
How are genetic defects caused?
By inheritance of an allele (such as in hemophilia) or It can be caused by chromosomal abnormalities
How do chromosomal abnormalities occur?
They result when the inherited genome is missing a chromosome or has an extra chromosome (both from nondisjunction), or when one or more chromosomes have portions deleted (called a DELETION), duplicated (DUPLICATION), moved to another chromosome (TRANSLOCATION), or rearranged in reverse orientation on the same chromosome (INVERSION)
What are the 5 main ways chromosomal abnormalities can occur?
What is the classic case of nondisjunction?
Down Syndrome: which is caused by trisomy of chromosome 21.
True or false: Most monosomies and trisomies are lethal?
What is monosomy and trisomy?
Monosomy = A Zygote that has one copy of a chromosome (2N-1)

Trisomy = A Zygote that has three copies of a chromosome (2N +1)
What are mutations?
Are changes in the genetic information of a cell, coded in DNA.
Mutation that occur in somatic cells lead to....

2) Mutations that occur in sex cells (gametes) will be transmitted to ______
1) lead to tumors
2) transmitted to the offspring
T or F: Most mutations occur in regions of DNA that do not code for proteins and are silent (not expressed in the phenotype)
Mutations that do change the sequence of amino acids in proteins are most often _____ and _______
recessive and deleterious
What are mutagenic agents and what are the types? ANd most agents are _______
Mutagenic agents induce mutations.

- cosmic rays
- x-rays
- radioactivity
- chemical compounds like colchicine (which inhibits spindle formation, therby cuasing polyploidy), or mustard gas

THey are usually carcinogenic
What are mutations types?
IN a gene mutation, nitrogen bases are :
1) added
2) deleted
3) or substituted
This genetic disorder is the inability to properly break down the amino acid-Phenylalanine. Accumulation of phenylalanine in untreated children causes mental retardation. Symptoms can be avoided with diets low in phenylalanine.:

A. Sickle-cell anemia
B. Duchenne's muscular
C. Phenylketonuria
D. Down Syndrome

State the patter on inheritance
C. Phynalketonuria

Pattern =autosomal recessive
This is an anbnormal hemoglobin
A. Sickle-cell anemia
B. Duchenne's muscular
C. Phenylketonuria
D. Down Syndrome

State the patter on inheritance
A. Sickle-Cell Anemia

Pattern = Autosomal recessive
This is the inability to properly break down certain lipids. Accumulation of the lipids in brain cells causes progressive nervous system dysfunction an dis usually fatal by age four.

A. Sickle-cell anemia
B. Duchenne's muscular
C. Phenylketonuria
D. Down Syndrome
E. Tay-Sachs disease

State the patter on inheritance
E. Tay-Sachs

Pattern = autosomal recessive
THis genetic deffect is the expression begins in middle age with mild mental illness and loss of motor control progressing to total physical and mental incapability.

A. Huntington's Disease
B. Duchenne's muscular
C. Phenylketonuria
D. Down Syndrome

State the patter on inheritance
A. Hungtingon's disease

Pattern = autosomal dominant
This is the inability to code for clotting factor requried to from normal blood clots

A. Sickle-cell anemia
B. Duchenne's muscular
C. Phenylketonuria
D. hemophilia

State the patter on inheritance
D. hemophilia

sex-linked recessive
This is the inability to distinguish red from green

A. Sickle-cell anemia
B. Duchenne's muscular
C. red-green color blindness
D. hemophilia

State the patter on inheritance
C. red-green color blindness

sex-linked recessive
This is the absence of an essential muscle protein. Results in dystrophy deteriorating muscles and loss of coordination

A. Sickle-cell anemia
B. Duchenne's muscular
C. Phenylketonuria
D. Down Syndrome

State the patter on inheritance
B. Ducheene's

sex-linked dominant
This genetic defect is the trisomy 21 (three copies of chromosome 21). Physical abnormalities, mental retardation

A. Sickle-cell anemia
B. Duchenne's muscular
C. Tay-Sachs
D. Down Syndrome

State the patter on inheritance
D. Downs

nondisjunction of chromosome 21
This is XO and female. Union of gamete missing the sex chromosome with a normal egg or sperm bearing an X chromosome.

A. Sickle-cell anemia
B. Duchenne's muscular
C. Turner Syndrome
D. Down Syndrome

State the patter on inheritance
C. Turner Syndrome

nondisjuction of sex chromosomes
XXY and male. Union of XX gamete and normal Y gamete. Sterile and often mentally retarded

A. Sickle-cell anemia
B. Klinefelter syndrome
C. Phenylketonuria
D. Down Syndrome

State the patter on inheritance
B. Klinefelter syndrome

nondisjunction of sex chromosomes
Physical and mental retardation and catlike cry.

A. Cri du chat syndrome
B. Turner Syndrome
C. Phenylketonuria
D. Down Syndrome

State the patter on inheritance
A. Cri du chat syndrome

deletion in chromosome 5
Suppose that in sheep, a dominant allele (B) produces black hair and a recessive allele (b) produces white hair. If you saw a black sheep, you would be able to identify

a. its phenotype for hair color
b. its genotype for for hair color
c. the genotypes for only one of its parents
d. the genotypes for both of its parents
e. the phenotypes for both its parents
A. Its phenotype for hair color

All you know that the sheep will be black b/c either of the parents could all types of genotypes and phenotypes.
From the cross CCSS x ccss, what is the probability of having an offspring that is CcSs?
100% or 1

recognize this type of pattern
From the cross CcSs x CcSs, what is the probability of having offspring that is ccss?
know that 9:3:3:1 ; the whole is 16

And you know that 1 is completeltly recessive (ccss).
So... 1/16 is your answer
From cross CcSs x CcSs, what is the probability of having an offspring that is normal for both traits? (knowing that C and S will yield normal)
know that 9:3:3:1

So 9/16 are normal
The inheritance of skin color in humans is an example of which of the following?

A. Pleiotropy
B. Codominance
C. Epistasis
D. Polygenic inheritance
E. Gene linkage
D. Polygenic inheritance; since the range of skin colors in humans shows continuous varation from very pale to very dark, it is most likely coded by many genes (polygenic inheritance)
Red-headed people frequently have freckles. What best explains this?
The genes for these two traits are linked on the same chromosome.

When two traits frequently occur together, then they are probably linked. Sometimes, a red-headed person my not hvae freckles, or a freckled person may not have red hair. IN these cases, there wsa probably a crossover event, exchaning one of the two genes with an alele that did not code for freckles or red hair.
True or false: In domestic cats, two alleles of a sex-linked (x-linked) gene code for hair color. One allele codes for yellow hair, and the other allele codes for black hair. Cats can be all yellow or all black, or they can be calico, a coat characterized by randomly arranged patches of yellow and black hair. With repsect to this gene, this is true:

A Calico female and a yellow male can produce a male calico cat.
False: In order to be calico you must have both X^B (black) and X^Y (yellow) alleles. Males can only have one X allele. Therefore they can only be yellow or black; never calico.
DNA and RNA are polymers of what?

A, Amino Acids
B. Nucleotides
B. Nucleotides
A nucleotide is a:

monomer or polymer

And what does it consists of?
A monomoer consisting of a nitrogen base, a sugar, and a phosphate group.
For DNA label the following components:
1) Nucleotide components (sugar and nitrogen bases)
2) Function
3) Structure
1) Sugar = deoxyribose
Nitrogen bases=CTAG
2) contains hereditary information (genes) of the cell
3) double helix
For RNA label the following components:
1) Nucleotide components (sugar and nitrogen bases)
2) Function
3) Structure
1) Sugar = ribose
Nitrogen bases = CUAG
2) 3 Functions of RNA and their structure

1) mRNA-provies the instructions for assembling amino acids into a polypeptide chain. STRUCTURE = LINEAR

2) tRNA = delivers amino acids to a ribosome for their addition into a growing polypeptide chain. STRUCTURE = "clover leaf" shaped

3) rRNA - combines with proteins to form ribosomes. STRUCTURE = globular
How many kinds of DNA are there?

How many kinds of RNA are there?

3 (mRNA, tRNA, and rRNA)
In DNA replication semiconservative means that____
Each new daughter helix contains an intact strand from the parent helix and a newly synthesized strand
Walk through the 9 abbreviated steps of DNA synthesis
1) Helicase = separates DNA into two strands (leading (3->5) lagging (5->3()
2) SSB's coat string to DNA from reforming
3) Topoisomers = straighten out kinks
4) RNA Primase = synthesize RNA Primer
5) DNA polymerase = extends DNA strand (always builds 5 -> 3) direction
6) Sliding clamp = increase processivity
7) RNAse H = remove RNA primer (nucleotides)
8)DNA polymerase = fills in gap with DNA nucleotides
9) ligase = connects short DNA strands, created by Okazaki fragments.
DNA replication occurs where and during what phase? be specific
Occurs in nucleus, during interphase durin the S phase.
The language of DNA consists of how many "LETTERS"?

THe language of PROTEINS (amino acid language) consists of how many "WORDS"?
four: ATCG

PROTEINS: 20 words: the 20 amino acids
How is the DNA language translated to produce 20 words in the amino acid language?
The DNA language must be translated my "mRNA" in such a way as to produce the 20 words in the amino acid language; hence, the triplet code.
How is the base sequence of mRNA translated? And what are these called?
mRNA is translated in a series of triplets called "codons"
How do mutations occur in DNA?
If a DNA error is not reparired = mutation
What kinds of mutations are there?
incorrect nucleotide = substitution

2) a missing nucleotide = deletion

3) an additional nucleotide not present in the original DNA molecule = insertion
What happens when an insertion occurs in DNA?
it causes all the subsequent nucleotides to be displaced one position, producing a frameshift mutations.
Radiation or chemicals that cause mutations are called
_________are mutagens that activate uncontrolled cell growth (cancer)
What types of instructions does DNA contain?
DNA in chromosomes contains instructions that regulate development, growth, and the metabolic activities of cells.

THe DNA instructions tells whether a cell will be that of a pea plant, human, or something specific to that organism.
How does DNA control the cell?
it contains codes for polypeptides. Many polypeptides are enzymes that regulate chemical reactions, and these chemical rxns influence the resulting charatersitic of the cell.
The process that describes how enzymes and other proteins are made from DNA is called...
Protein synthesis
What are the three steps to protein synthesis? briefly describe each of the steps (generally)
1) transcription = RNA molecules are created by using the DNA molecule as a template.
2) RNA processing = RNA processing modifies the RNA molecule with deletions and additions
3) translation- the processed RNA molecules are used to assemble amino acids into apolypeptide.
during which phase of protein synthesis are the three kinds of RNA molecules produced? What are those three?

1) mRNA
2) tRNA
3) rRNA
RNA kind be found where?
in both the nucleus and cytoplasm and is usually single stranded unlike DNA.
DNA -> DNA is known as...
2) DNA -> RNA
3) RNA -> Protein

WHich direction are they all synthesized?

DNA synthesized 5' -> 3' direction
2) new RNA synthesized in 5' -> 3' direction
3) mRNA read in 5' -> 3' direction
Where are each of these synthesized?
1) tRNA
2) mRNA
3) rRNA
tRNA and mRNA = synthesized in the nucleus

rRNA = synthesized in the NUCLEOLUS
What is
1) mRNA
2) tRNA
3) rRNA
1) mRNA = is a single strand of RNA that provides the template used for sequencing amino acids into a polypeptide.

2) tRNA = is a short RNA molecule that is used for transporting amino acids to their proper place on the mRNA template.

3) rRNA molecules are the building blocks of ribosomes.
What are the characteristics of mRNA?
A. FUNCTION: Acts as a template used for sequencing amino acids

B. STRAND: single
D. monocistronic = one mRNA strand codes for one polypeptide
H. Has 5'-cap (-P-P-P-G-5). Purpose is to provide mRNA stability and a point of attachment for small RNA subunit.
I. Has poly-A tail. purpose provides stability and helps move mRNA through nuclear envelope out to cytoplasm.
J. mRNA has segments: exons and introns (snRNP's delete out introns)
What are the characteristics of tRNA?
A. FUNCTION: is a short RNA molecule that is used for transporting amino acids to their proper place (code) on the mRNA template
B. SHAPE: 'three-clover = 3-dimensional
D. Contains Anti-codon
E. Has amino acid attachment
F. In cytoplasm, amino acids attach to the 3' end of the tRNAs, forming aminoacyl-tRNA. The reaction requires an enzyme specific to each tRNA (aminoacyl-tRNA synthetase) AND the energy from one ATP.
G. The amino acid-tRNA bond that results is a high-energy bond, creating and "activated' amino acid-tRNA complex.
What are the characteristics of rRNA?
A. FUNCTION: rRNA molecules are the building blocks of ribosomes.
B. SYNTHESIZED: nucleolus
How are ribosomes made and what is there part in protein synthesis?
Ribosomes are made within the nucleolus. In there, various proteins are imported from the cytoplasm and are assembled with rRNA to from large and small ribosomal subunits. Together, the two subunits form a RIBOSOME, which coordinates the activities of the mRNA and tRNA during translation.

The small ribosomal subunit + mRNA + tRNA = initiates translation.

The Large ribosomal subunit follow shortly. The large has 3 sites: A, P, E
After transcription what three things are transported across the nuclear envelope?
mRNA, tRNA and ribosomal subunits (small and large)
In protein synthesis go through the steps of Transcription for me
1) Initiation:
A. RNA polymerase attaches to promoter regions on DNA = unzips
B. Promoter region for mRNA: T-A-T-A

A. RNA polymerase assembles RNA nucleotides using 1 DNA strand as a template
B. RNA synthesized 5'->3' direction

3) Termination:
A. RNA Polymerase reads termination stop codon on DNA = AAAAAAA
In protein synthesis go through the steps of RNA Processing for me.
Before mRNA leave nucleus it goes through two kinds of alternations

Alteration 1:
Both ends of the mRNA get attachments
A. 5' end gets a 5'-cap which is a guanine nucleotide molecule (GTP). This provides stability and a point of connection for the small ribosomal subunit
B. THe 3' end gets a poly-A tail. Provides stability and helps get through the nuclear envelop.

Alteration #2:
A. mRNA segments are removed
B. entons = coded
C. introns = noncoded
These are deleted by snRNP's before leaving the nucleus.
In protein synthesis walk me through Translation
Before that tRNA is doing is thing out in the cytoplasm, after leaving the nucleus and transcription. tRNA finds amino acids that are floating around and attaches to them (specifically) = forming aminoacyl-tRNA. This specific reaction is helped by aminoacyl-tRNA synthetase. tRNA is now Activated and ready to go.

1. Small Ribosomal Subunit attached to 5' end (GTP) of mRNA.

2. tRNA (with anticodon UAC) carries amino acid Met attaches to mRNA at start codon (AUG), with hydrogen bonds

3. Large Ribosomal Subunit attaches to the mRNA, forming a complete ribosome with the tRNA (bearing Met) occupying the P site.

4. A different aminoacyl-tRNA attaches at A site and a peptide bond is formed between Met and the new amino acid that tRNA brought in. The A site turns into peptidyl-RNA. then shifts into the P site, freeing up space for another aminoacyl-tRNA to land on A site. process is repeated.

5. The P site then shifts to the E site where the tRNA (no longer aminoacyl-tRNA) goes back into the cytoplasm to pick up more aminoacids.

6. Ribosome encounters one of three stop codons.

Large and small ribosomal subunits and mRNA are released. They can go through this again if they would like.
What energy is used during translation?
In eukaryotes how is DNA organized?
The DNA is packaged with proteins called Histones to form DNA-histone complexes called NUCLEOSOMES (look likes beads)
How is a nondividing cell organized?
Two ways
1) Euchromatin: describes regions where DNA is loosely bound to nucleosomes. DNA in these regions are being actively transcribed.

2. Heterochromatin: areas where nucleosomes are more tightly compacted, and where DNA is inactive. Stains Darker because more dense.
2) Heterochromatin
List all of the places DNA is found in a eukaryotic cell?
What are viruses?
Parasites of cells
WHat are bacteriophages or phages?
Viruses that ONLY attack bacteria
What parts make up a virus?
- nucleic acid (DNA OR RNA)
- surrounded by coat protein called CAPSID.
- some capsids have ENVELOPE, that helps penetrate hose cell
What are the two basic replication cycles of viruses?
1) lytic cycle
2) lysogenic cycle
Bacteriophages that replicate by the lytic cycle, killing their host cells, are said to be
Describe the Lytic cycle
Virus penetrates teh cell membrane of the host cell and nused the enxymes of the host cell to replicate viral DNA, transcribes viral DNA into RNA, and translates the RNA into proteins.

Host cell lyses and infects other cells doing the same thing.
Describe the lysogenic cycle
Viral DNA temporarily incorporated in Hosts cell. A virus that is dormant, causing no harm, is a PROVIRUS (OR if a bacteriophage a PROPHAGE)
What is a retrovirus?
A type of virus that uses an enzyme called reverse transcriptase to make a DNA complement of the virus's RNA. From it can enter either lytic or lysogenic cycle
T or False Bacteria are eukaryotes?
False, Prokaryotes
What is bacteria made of and how does it reproduce?
No nucleus
No spindle apparatus
No microtubules
No centrioles
No histones (proteins invloved with DNA structure)
Yes single Circular DNA Molecule
Yes Plasmids = short, circular DNA molecules outside the chromosome, which contain accessory genes.
What are episomes and who has them?
Bacteria have them. They are plasmids that are capable of integrating into the bacterial chromosome
How is bacteria replicated?
proceeds in both direction. simultaneously. DNA is synthesized in the 5'->3' direction
How do bacteria cells reproduce?
Binary Fission (asexual process)
How does bacteria get genetic variance?
Three ways
1. transformation
2. conjugation
3. transduction
What is transformation related to bacteria?
Method of bacterial genetic variance. Transformation occurs when bacteria absorb DNA from their surroundings.
What is transduction in relation to bacteria?
A method of bacterial genetic variance. Transduction occurs when new DNA is introduced into bacteria by a virus
What is conjugation in relation to bacteria?
Process by which DNA is exchanged between bacteria = like SEXAUL MATING.

A cytoplasmic conjugation bridge is formed between two cells and genetic material is transferred from the donoer male (+) to the recipient female (-) type. Only bacteria containing plasmids called sex factors are capable of conjugating.
What are two examples of conjugation sex factors?
1) F Factor in E. coli.
2) R Factor that provide bacteria with resistance against antibiotics
How do prokaryotes control their metabolism? And is this only found in prokaryotes?
The regulation of gene expression (transcription)

This can also be found in prokaryotes?
What is an operon
In bacteria they contain sequences of DNA that direct certain biosynthetic pathways. Regulation of a gene expression (transcription) enables prokaryotes to control their metabolism.
What are the four parts/regions of an operon?
1) regulatory gene = PRODUCES a repressor protein, a substance that can prevent gene expression by blocking the acton of RNA polymerase
2) promoter = is a sequence of DNA to which the RNA polymerase attaches to begin transcription
3) operator = can block the action of the RNA polymerase if the region is occupied
4) structural genes = contain DNA sequences that code for proteins
If RNA polymerase bind to promotor ->

2) Repressor bind to operator ->

3) Inducer binds to repressor -> A -> B
1) structural genes transcribe

2) structural genes NOT transcribed

3) #1 no binding to operator -> #2 structural genes transcribed
Why are lethal dominant alleles much less common than lethal recessive alleles?
Because the lethal dominant allels usually kill the person, thus the dominant allele dies with them and not passed on. But a person can be a carrier of a lethal allele as long as it is recessive. Those can be passed b/c the host does not die
What are the three differences between DNA and RNA ?
DNA double stranded; RNA singl
2) deoxyribous : RNA ribose
3) DNA: T nitrogen base; RNA U nitrogen base
Walk me through the Hormones and the female reproductive cycle.
1) The hypothalamus and anterior pituitary initiate the reproductive cycle.
2) The follicle develops
3) the follicle secrets estrogen
4) Ovulation occurs
5) THe corpus luteum secretes estrogen and progesterone
6) The endometrium thickens
7) The hypothalamus and anterior pituitary terminate the reproductive cycle
8) The endometrium disintegrates
9) If implantation occurs the implanted embryo sustains the endometrium
How many hours can an oocyte be fertilized after ovulation?

Egg and sperm fused =
12-24 hours

In early development the zygote begins a series of rapid______. What is the purpose of that?
rapid CLEAVAGES. This means rapid cell divisions without cell growth. Meaning the total cell cytoplasm is constant
T or F cleavage in embryonic development also increases the surface-to-volume ratio of each cell, thereby improving gas exchange and nutrient exchange
What is an intermediate cleavage? WHat is an example?

What is an determinate cleavage?
Indeterminate Cleavages produce blastomeres that if separated results in cells that maintain the ability to develop into a complete organism.
Identical twins are a result of indeterminate cleavage

Determinate cleavage results in cells (blastomeres) whose future differentiation pathways are determined at a an early developmental stage.
At fertilization take me through the cleavage steps through the end.
Fertilized egg
-> 2-cell stage
-> 4 cell stage
-> 8 cell stage
-> 16 cell stage
-> morula
-> Blastula
What is the a morula?
A solid ball of cells as a result of successive cleavage

Blastula: As cell divisions continue, liquid fills the morula and pushes the cells out to form a circular cavity surrounded by a single layer of cells. This hallow sphere of cells is called the blastula, and the cavity is the BLASTOCOEL
When does gastrulation occur?
Once implanted in the uterus, cell migrations transform the single cell layer of the blastula into a two then three-layered structure called gastrula
What are the three primary germ layers in the blastula?
Name the parts
State which germ layer these originate from:
circulatory system
Hair = ectoderm
thyroid = endoderm
circulatory system = mesoderm
epidermis = ectoderm
State which germ layer these originate from:
epithelial linings of digestive and respiratory tracts
excretory system
nervous system
musculoskeletal system
epidermis = ectoderm
epithelial linings of digestive and respiratory tracts = endoderm

excretory system = mesoderm
musculoskeletal system = mesoderm
nervous system = ectoderm
What are the four extraembryonic membranes that develop during development?
yolk sac
What are the two main components to the specialized circulatory system in placental internal development for humans and most mammals?
The placenta and umbilical cord

Placenta: s a blend of maternal and embryonic tissues across which gases, nutrients, and wastes are exchanged.

Umbilical Cord: Transport gases, nutrients, and swastes between the embryo and the placenta
WHat is the chorion and what originates from it?
The chorion is the outer membrane. The chorion with other maternal tissues forms the placenta.
How is the umbilical cord made?
It originates from the allantois
What is the allantois?
It begins as a sac that buds off from the archenteron. It encircles the embryo forming a layer below the chorion. Later it fuses with chorion which leads to the development of the umbilical chord. (note that the chorion turns into the placenta)

- Also The blood vessels of the allantoic wall enlarge and become the umbilical vessels, which will connect the fetus to the developing placenta.
WHat is the amnion?
surrounds the embryo and is filled with fluid that cushions
What is the yolk sac for Placental mammals and for birds and reptiles?
Placental mammals = yolk sac is empty. Nutrition is obtained from placenta. It is also the site of early development of blood vessels.

in Birds and Reptiles: Provide nutrients for them.
What and where are acrosomes? What do they do?
Found on tip of sperm head.
- a lysosome containing enzymes that can penetrate the egg.
How is circulation accomplished with: Protozoans
movement of gases and nutrients is accomplished by simple diffusion within the cell
How is (gas exchange) circulation accomplished with: Cnidarians (is this a Phylum or class etc? Give some organism examples)
Cnidarians = Phylum
Examples = jellyfish, corals

Circulation = They have body walls that are two cells thick. All cells are in direct contact with either the internal or external environments so there is no need for specialized circulatory system.
How is circulation accomplished with: Arthropods ( is this a phylum, kingdom, class, order, family etc? Give some organism examples)
Arthropods = Phylum
Examples = butterfly, centipede, scorpion

Gas exchange = Arthropods have OPEN CIRCULATORY SYSTEMS in which blood (interstitial fluid) is in direct contact with the body tissues. The blood is circulated by boy movements. Blood flows through a DORSAL VESSEL and into spaces called SINUSES where exchange occurs.
How is circulation accomplished with: ANNELIDS ( is this a phylum, kingdom, class, order, family etc? Give some organism examples)
Annelids = Phylum
Examples = segmented worms, earth worms, leeches

Gas exchange = Closed Circulatory system. Blood is confined to vessels. Blood moves towards the head in the dorsal vessel which functions as the main heart by coordinated contractions.
- 5 pairs of vessels called aortic loops connect the dorsal vessel to the ventral vessel and function as additional mumps.
- Earthworm blood lacks any red blood cells. But has hemoglobin-like pigment that is dissolved in aq solution.
The right side of the heart pumps deoxygenated blood into ______

THe left side of the heart pumps oxygenated blood into ________
1) pulmonary circulation (toward the lungs)

2) systemic circulation (through out the body)
Describe each of the following:
thick-walled, muscular, elastic
VEINS: thin-walled, inelastic, conduct deoxygenated blood towards heart
What is the primary and secondary circulations systems?
Primary = blood vessels
Secondary = lymph vessels
What do lymph vessels do?

What are lymph nodes
transport excess interstitial fluid, called lymph, to the cardiovascular system, thereby keeping fluid levels in the body constant.

Lymph Nodes = swellings along lymph vessels containing phagocytic cells (leukocytes) that filter lymph , removing and destroying foreign particles and pathogens
Where where are leukocytes found and what is their main purpose?
found in lymph nodes. They filter lymph, removing and destroying foreign particles and pathogens
WHat is plasma and what is in it?
the liquid portion of blood. An aqueous mixture of:
nutrients, salts, respiratory gases, wastes, hormones, and blood proteins (eg. immunoglobulins, albumin, and fibrinogen)
What are the two components of blood?
liquid (55%) and cellular (45%)
What does the cellular component of blood consist of?
erythrocytes, leukocytes, and platelets
What are erythrocytes:
Where they are recycled:
Erythrocytes = red blood cells

Function: carry oxygen by one of 250 million molecules of hemoglobin on one red blood cell. hemoglobin + oxygen = oxyhemoglobin.

Structure: biconcave, disk-like shape (very efficient)

Originate: formed from stem cell in the bone marrow. They lose nuclei, mitochondria, and membraneous organelles.

Where they are recycled: After about 120 days they are phagocytized by special cells in the SPLEEN AND LIVER
Where they are recycled:
Function: protective
- Phagocytize foreign matter like bacteria
- Migrate to blood tissue and remain stationary = macrophages
- Involved in immune response and the production of antibodies (B cells) or cytolysis of infected cells (T cells)
Structure: larger than erythrocytes
Originate: Bone marrow
Where they are recycled:
What are platelets?
Found in cell component of blood. Platelets are cell fragments that lack nuclei and are involved in clot formation.
WHat are the main functions of:
Blood: transports nutrients and O2 to tissue, and wastes and CO2 from tissue

Platelets: injury repair

Leukocytes: MAIN component of the immune system.
How many molecules of O2 can each molecule of hemoglobin bond to?
1 hemoglobin can bond to 4 O2 molecules
T or False: Hemoglobin also bind to CO2
What types of pathogens can possibly harm our body
bad proteins
In Immune response what is our first line of defense?
Antimicrobial agents (in saliva, tears and mucus)
- cilia in lungs
- gastric juice
- symbiotic bacteria found in Vagina that out compete any foreign agent.
WHat is our second line of defense in immune response?
Inflammatory response
What is the difference between non-specific and specific immune response?
non-specific: is usually our first and second line of defense. They don't remember what type of pathogen they are attacking or know what "specific" type it is. They simply realize that ..."hey, you are not supposed to be here. I am going to kick you out."

Specific immune response. It targets specific antigens
The inflammatory response can be generally termed as...
"bringing weapons to the fight."
What are the most common types of Phagocytes?
Neutrophils = fast and abundant
Monocytes = enlarge into large phagocytic cells called macrophages
Macrophages = versatile, heavy lifters
- Natural killers (NK Cells) attack abnormal body cells (such as tumors) or pathogen-infected body cells
- Dendritic cells good with turning into specific immune response
What are "complement" in the immune response?
is in non-spedific secondary response. is a group of about twenty proteins that "complement" defense reactions.
- proteins help attract phagocytes to foreign particles and help destroy foreign cells by promoting cell lysis (breaking open the cell)
WHat are interferons and how are they involved in the immune system?
non-specific and part of secondary response.
- substances secreted by cells invaded by viruses that stimulate neighboring cells to produce proteins that help them defend against the viruses.
- like calling 911
True or false phagocytes and lymphocytes are leukocytes (white blood cells)
Lymphocytes have two other sub lymphocytes called...
B Cells- from the bone marrow (B for bone marrow)

T Cells - come from bone marrow but mature in the thymus
What are B cells and what type of immunity are they involved with?
Humoral Immunity:
Originate and mature in bone marrow
- Have Y-antibodies on them (which are specialized receptors for antigens = foreign particles)
1) Antibodies are also known as
1) immunoglobulins
What are the properties of antibodies:
1) Antibodies are proteins
2) Each antibody is specific to a particular antigen
3) There are 5 classes of antibodies (IgA, IgD, IgE, IgG, IgM)
4) Each class is a variation of the basic y-shaped protein that consists of constant regions and variable regions. The variable regions are sequences of amino acids that differ among antibodies and give them specificity to antigens
5) Antibodies inactivate antigens by binding to them -> followed by phagocytosis
Why are there so many variable portions on the membrane-bound antibodies on B cells?
So that at least one will be able to identify a foreign object/antigen. B/c there is so much out there that could harm us so this is our bodies way of preparing us for whatever comes.
What is the process of clottingi?
1) Platelets in contact with exposed collagen
2) platelets release thromboplastin
3) thromboplastin converts inactive prothrombin -> active thrombin
4) Thrombin (converts) -> fibrinogen -> fibrin

5) Fibrin coats the damaged area and trap blood cells to form a clot.
More condensed version of the clotting process
Cut -> platelets release thromboplastin -(conv)> prothrombin -> thrombin -> fibrinogen -> fibrin -> traps blood cells and forms clot

The fluid left after blood clotting = serum
Person who is Rh+ is said to what

A person who is Rh- is said to what?
1) Rh+ = individuals posess the Rh antigen on the surface of their RBC's

2) Rh- = the individual is lacking the Rh antigen on their RBC's surface
Explain the Rh Factor scenario with a mother and child. WHat happens?
Rh- Mom has Rh+ baby
-> Rh- mom, sensitized, develops Rh+ antibodies

Rh- mom has another Rh+ baby
-> The Rh+ antibodies that mom developed from the first child attacks the blood of the second child
killing the fetus or severe anemia called erythroblastosis fetalis
What do the vascular bundles in plants consist of?
xylem, phloem and cambium cells.
What is the purpose of xylem and phloem?
xylem conducts water and minerals UP the and also provides mechanical support

phloem is conducts sugars
What two types of xylem cells can xylem differentiate into?
1) vessel cells: shorter and wider, have less or no taper at ens (have perforations = water moves better on vessels than tracheids)

2) tracheids: long and tapered (passes through one tracheid to another through pits)
What are the three ways that the xylem pulls water up?
1) Transpiration pull - as water evaporates from the leaves of plants, a vacuum is creaetd which pulls water up the stem

2) Capillary action- any liquid in a thin tube will rise due to the surface tension of the liquid and interactions between the liquid and the tube.

3) Root pressure - water entering the root hairs exerts a pressure which pushes water up the stem.
The Phloem cells are living and include two types of cells
sieve tube cells: form sieve-tube members tha form fluid-conducting columns call sieve tubes. L
- Living, but lack nuclei and ribosomes
- Pores on the end walls of sieve-tube member form sieve plates, areas where the cytoplasm of one cell makes contact with that of the next cell.

companion cells:
-living parenchyma cells that lie adjacent to each sieve-tube member.
- connected to adjaent sieve-tube members by tin tubes of cytoplasm called plasmodesmata, maintain physiological support to the nuclei-lacking sieve-tube members.
If a tree is girdled by removing a strip of bark around the trunk, the ______connections are severed and the tree will _____
phloem, die
What are the three main tissues of plants?
1) Ground tissues
A. Parenchyma cells
B. Collenchyma cells
C. Sclerenchyma cells
2) Dermal Tissues
3) Vascular Tissues
A. xylem
B. phloem
Ground tissues include what three types of cells...describe each.
1) Ground tissues
A. Parenchyma cells: the most common component of ground tissue, have thin walls and serve various function including storage, photosynthesis, and secretion

B. Collenchyma cells:
have thick but flexible cell walls, serve mechanical support functions

C. Sclerenchyma cells:
with thicker wall than collenchyma, also provide mechanical support functions
For Monocots:
Leaf Venation:
Flower Parts:
VAscular bundles:
For Monocots: ie corn, wheat, sugar cane

Cotyledons:1 cotyledon
Leaf Venation: parallel
Flower Parts: in 3's or multiples thereof
VAscular bundles: scattered xylem and phloem)
Root:fibrous system ( a cluster of many fine roots)
For dicots:
Leaf Venation:
Flower Parts:
VAscular bundles:
For Dicots:
Cotyledons: 2 cotyledons
Leaf Venation: netted (a branching pattern)
Flower Parts: in 4's, 5's or multiple thereof
VAscular bundles: organized in a circle
Root: taproot (a large single root)
What are the parts to a plant embryo?
1. epicotyl = embryo top portion = becomes root tip
2. plumule = leaves attached to epicotyl
3. hypocotyl = become young shoot
4. In some embryos, a radicle develops below the hypocotyl. The radicle develops into the root
5. In many monocots, a sheath called the coleoptile surround and protect the epicotyl. = appears as leaf
What is the cambium?
Cambium cells (two layers thick) are the actively dividing, undifferentiated cells which give rise to xylem and phloem. Cells close to the xylem form into xylem. cambium cells close to phylum form into phylum.
What is the difference between primary and secondary growth in plants?
Primary growth: occurs in young plants. Growth occurs in the vertical direction

Secondary growth: Plants like conifers and woody dicots not only grow vertically through apical meristems but through lateral meristems = origin of woody plant tissues.

Secondary growth occurs at two lateral meristems: vascular cambium and the cork cambium
Cork cambium gives rise to what?
the periderm = the protective material that lines the outside of woody plants
What are the specialized tissues for the primary structure of a root?
1. Epidermis = lines the outside surface of the root.
- Zone of maturation (or differentiation) epidermal cells produce root hairs, which increase the absorptive surface of the roots.

2. Cortex = bulk of the root, main function is the storage of starch

3. Endodermis= ring of tightly packed cells.
- suberin- a fatty substance that creates a water-impenetrable barrier called the casparian strip.
= Result = all water must go through endodermal cells.
= means = endodermal cells can control movement of water

4. Vascular cylinder, or stele: Tissues inside endodermis
identify these structures
Cork cambium produces ->
vascular cambium produces ->
the periderm = bark
xylem and phloem
What plant vascular tissue makes up the wood of the plant?
2) The xylem that is produced during the more recent years remains active in the support of water =
3) Older xylem, located toward the stem =
1) the xylem
2) sapwood
3) heartwood = provides support
THe annual rings of a tree are from what?
the xylem
Identify the different layers and components
What is a leaf covered witih?
waxy cuticle (material is called cutin)
WHat is palisade mesophyll
consists of parenchyma cells equipped with numerous chloroplasts and large surface areas, specializations for photosynthesis. Photosynthesis in leaves occurs primarily in this tissue. The parenchyma cells are usually tightly packed in one or more layers at the supper surface but can occur at both surfaces in leaves of plants adapted to dry habitats.
What is spongy mesophyll?
consists of parenchyma cells loosely arranged below the palisade mesophyll. THe numerous intercellular spaces provide air chambers of plants that provide CO2 to photsynthesizing cells (and O2 to respiring cells)
What are guard cells?
are specialized epidermal cells that control the opening and closing of the stomata. Stomata are openings in the epidermis that allow gas exchange between the inside of the leaf and the external environment
WHat are the two ways that water moves toward the center of the root?
1) apoplasts = nonliving = water moves through cell walls from one cell to another

2) symplasts = living = moves the cytoplasm of one cell to the cytoplams of the next through pasmodemsmata, small tubes that connect the cytoplasm of adjacent cells
How is the opening and closing of the stomata regulated?
1) Stomata closes when Temps are high (closed photosynthesis stops)
2) Stomata opens with CO2 is low (photosynthesis starts)
3) Stomata close at night and open during the day
4) Stomatal opening accompanied by diffusion of potassium ions (K+)
What are the 5 classes of plants hormones?
1) Auxin (IAA)
2) Gibberellins
3) Cytokinins
4) Ethylene
5) Abscisic acid (ABA)
What is the the function of auxin?
Plant hormone
- promotes plant growth by facilitating the elongation of developing cells
- produced at the tips of roots and shoots and, along with other hormones, influences phototropism and geotropism.
- auxin is active in leaves, fruits and germinating seeds
- Actively transported (requiring ATP) from cell to cell.
What is phototropism and geotropism?
Phototropism = plants repsone to light

geotropism = plants response to gravity
What are gibberellins?
Plant hormone
- similar to auxin, by promoting plant growth etc.
- Main difference: has HIGH conc. of GA which causes rapid elongaton of stems called BOLTING.
-bolting occurs in rice plants when a fungus that produces GA attacks the plant.
What are cytokinins?
Plant Hormone:
- stimulate cytokinesis
- produced in roots
- can influence direction of organ development (organogenesis)
- can stimulate growth of lateral buds = apical dominance
- can delay senescence (aging) of leaves
What does ethylene do for plants?
- A Gas that promotes the ripening of fruit
What is abscisic acid (ABA)
Plant hormone:
growth inhibiter
- helps in dormant
Since plants can't move they can only change their growth patterns. A growth pattern in response to an environmental stimuli is called
What are the three types of tropism?
1) Phototropism
2) geotropism
3)Thigmotropism: is a response to touch. When vines and other climbing plants contact some object, they respond by wrapping around it.
What is photoperiodism?
Photoperiodism is the response of plants to changes in the photoperiod, or the relative length of daylight and night.
How do plants respond to changes in photoperiod?

What type of mechanism is this?
plants maintain a circadian rhythm, a clock that measures the length of day and night.

Endogenous mechanism: it is an internal clock that continues to keep time even if external cues are absent. It uses dawn and dusk to accurately reset its clock to account for any error
Describe the role of Phytochrome in a plants circadian clock?
1) Pfr appear to reset the circadian-rythm clock

2) Pr is the form of phytochrome synthesized in plant cells

3) Pr and Pfr are in equillibrium during daylight

4) Pr accumulates at night

5) At daybreak, light rapidly converts the accumulated Pr to Pfr

6) Night length is responsible for resetting the circadian-rythm clock
In response to stress what does the adrenal cortex synthesize and secrete?
The adrenal cortex synthesizes and secretes steroid hormones collectively known as CORTICOSTEROIDS.
Where are corticosteroids derived from and what do they include?
They are steroid hormones, derived from cholesterol.

cortical sex hormones
Posterior Pituitary
Target :
Posterior Pituitary
Location: Base of the brain. but get's its hormones from Hypothalamus. PP only stores them.
Hormone(s): oxytocin and ADH
Target :
-oxytocin = mammary glands
- ADH = Kidneys
- oxytocin = stimulates release of milk
- ADH = increases reabsorption of water
Anterior Pituitary
Type of Hormone:
Target :
Extra (overall) result:
Anterior Pituitary
Location: base of brain
Type of Hormone: Direct (PEG) and Tropic (FLAT)
Hormone(s): FLAT PEG
FLAT (Tropic)
- FSH = ovary, testes
- LH = ovary, testes
- ACTH = adrenal cortex
- TSH = thyroid
PEG (Direct)
- Prolactin = mammary glands
- Endorphines = general
- GH = bone, muscle

FLAT (Tropic)
- FSH = regulates oogenesis (maturation of ovarian follicles = estrogen secreted) and spermatogenesis
- LH = regulates oogenesis (simulates ovulation and formation of the corpus luteum) and spermatogenesis (tell males to synthesis testosterone)
- ACTH = secretion of glucorticoids (cortisol)
- TSH = secretion of T4 and T3
PEG (Direct)
- Prolactin = production of milk
- Endorphines = inhibit pain
- GH = stimulates growth
Extra (overall) result:
1) What can be said about a person with stunted growth?
2) What can be said about a person with gigantism
1) Dwarfism = under production of GH

2) Gigantism = Over production of GH
A disorder characterized by a disproportoinate overgrowht of bone, localized especially in the skull, jaw and feet and hand is

Over production of GH
Source: Alpha Cells ad B cells
Location:Next to kidney
- glucagon (a-Cells)
- insulin (b-cells)

- glucagon (a-Cells) = liver
- insulin (b-cells) = liver, muscles, fat
- glucagon (a-Cells): increases blood glucose
- insulin (b-cells): lower blood glucose
What are all of the hormones that increase plasma glucose?
Pancreas = glucagon
AC = glucorticoids (cortisol)
AM = epinephrine
Adrenal Cortex
Adrenal Cortex
Location: ON top of kindeys
-glucorticoids -> cortisol
-mineralcorticoids ->aldosterone
sex hormones -> androgens

-glucorticoids -> general
-mineralcorticoids -> kidney
sex hormones -> testes
-glucorticoids -> increase blood glucose
-mineralcorticoids -> increases reabsorption of Na+ and excretion of K+ (increases blood volume and pressure)

sex hormones -> male physiological effect
Adrenal Medulla (MEN)
Adrenal Medula
Location:above kidneys
- epinephrine
- norepinephrine

- epinephrine = blood vessels, liver, heart
- norepinephrine = same

- epinephrine: increases blood glucose, constricts blood vessels (fight or flight response)
- norepinephrine: SAME

CONTROLLED: regulated by ACTH from the AP
Location: on trachea
-thyroxin (T4)
-triiodothyronine (T3)

-thyroxin (T4) = gen.
-triiodothyronine (T3) = gen.
-calcitonin = bone

-thyroxin (T4) = Both T4 and T3 increase rate of metabolism necessary for growth
-triiodothyronine (T3)
-calcitonin = decreases Ca+2 in blood
1) Thyroid hormones are undersecreted or no secreted at all is
1) Common symptoms of hypothyroidism is:

2) Hypothyroidism in new born infants is called______. How is it characterized?
1) slowed heart rate and respiratory rate, fatigue, cold intolerance, and weight gain

2) cretinism: characterized by mental retardation and short stature
The thyroid is over stimulated resulting in over secretion of thyroid hormones _____
WHat are the symptoms of hyperthyroidism?
increased metabolic rate, feelings of excessive warmth, profuse sweating, palpitations, weight lose, and protruding eyes.
What do hyperthyroidism and hypthyroidism have in common most times?
Both often have enlarged thyroid, forming a bulge in the neck called a goiter
Location: on posterior surface of thyroid

Hormones: PTH

Target: bone, kidneys

Action: increases blood Ca+2 levels by stimulating Ca+2 release from bone and decreasing Ca+2 excretion in the kidneys
Hormones: testosterone

Target:testes, general

Action: spermatogenesis, secondary sex characteristics


-estrogen: uterus, general
-progesteron: uterus

-estrogen: menstrual cycle, secondary sex charact.

-progesteron: menstrual cycle pregnancy
Location: in the head
Hormones: melatonin
Target: body
Action: circadian rhythms
Location: next to pancreas
Hormones: renin
an enzyme that converts angiotensinogen to angiotensin I -> angiotensin II ->which, stimulates AC to secrete aldosterone.
Hormones: gastrin
Target: stomach
Action: ingested food stimulates the stomach to release gastrin. Gastrin tells gastrin glands to secrete HCL
Small Intestine
Small Intestine
- secretin
- cholecystokinin

- secretin = pancreas
- cholecystokinin = gall bladder

- secretin = released by small intestine when acidic food enters from the stomach. Secretin stimulates the secreation of alkaline bicarbonate solution from the pancreas which neutralizes the acidity of the chyme.

- cholecystokinin = is released from the small intestine in response to the presence of fats and causes the cnotractoin of the gallbladder and release of bile into the small intestine.

Bile is involved in the digestion of fats.
What is the difference between peptide hormones and steroid hormones
Peptide hormones:
- surface receptors
- generally act via secondary messengers (ie cyclic AMP)

Steroid hormones:
- intracellular receptors
- hormone/receptor binding to DNA promotes transcription of specific genes
What are the parts of the neuron?
cell body = has the nucleus and other cellular organelles.

dendrite = short , branched lots, receives stimuli

axon = long, SENDS nerve impulses
What produces myelin in the CNS and PNS?
CNS = oligodendrocytes
PNS = schwann cells
1) gaps between myelin are =
2) gaps between the axon terminals of once cell and the dendrites of the next cell =
3) what communicates between the axons and dendrites?
1) nodes of Ranvier
2) synapse
3) neurotransmitters
My finger gets pricked. What happens to the neuron? Go through the steps
Neuron receive signals from sensory receptors from other neurons
info is transferred along axon
Action potentials = impulses travel the length of the axon and invade the nerve terminal,
-> causing the release of neurotransmitter into the synapse.
The potential difference between the extracellular space and the intracellular space is called....
resting potential
1) neurons that receive initial stimulus?

2) target cells that produce some kind of response

3) located in the spinal cord or brain and receive impulses from sensory neurons or send impulses to motor neurons
1) sensory or afferent neurons

2) motor or efferent (efferent = means doing something)

3) association or internerons
When a neuron is at rest which side is more positive/negative. And which side to the Na+ and K+ ions reside?
Outside cell = Na+, more positive

Inside cell = K+, more negative
What ultimately contributes to the over negative charge in a neuron?
the large, negatively charged ions (proteins or nucleic acids), contribute to the over all negative charge of the cell membrane
True or false, a neuron is depolarized at rest?
What is the approximate mV of a resting potential?
True or false, the neuron membrane is selectively permeable?
Walk me through a stimulus from start to finish
1) Neuron Resting potential at -70mV, is polarized. Inside cell is negative with K+ and outside cell is positive with Na+

2) stimulus comes ->create action potential

3) Action potential:
-> gated ion channels open
-> Na+ rush IN
->cell is depolarized (more positive on the inside)(from -70 to 0)
-> if stimulus is above THRESHOLD LEVEL
-> more Na+gates open
-> more Na+ flows in
-> more Na+ gates are stimulated down the axon
Side NOTE: This is an ALL-OR-NOTHING EVENT: when a the stimulus fails to produce a depolarization that exceeds the threshold value, no action potential proceeds)

-> as Na+ flows in...
-> K+ ion channels open
-> K+ rushes OUTSIDE the cell
-> repolarizing the cell.

-By the time the K+ channels close more K+ is outside the cell than in
-> causes hyperpolarization, more negative than resting potential (-80 mV)

5. Refractory period:
-> we are at the opposite from where we started: more K+ is outside than inside.
-> the neuron will not respond to any more stimuli until it is back to normal = REFRACTORY PERIOD
-> Na+/K+ pumps use active transport (use ATP) to get the K+ back inside and the Na+ back outside
-> 3Na+ are pumped out for every 2K+ that are pumped in

Done: Everything is reset and the neuron is now at resting potential (-70mV)
Okay...now an action potential is coming from the dendrite through, axon ending at the axon terminal. What happens next?
neurotransmitters must cross the synapse between the axon terminal end and a different dendrite.
Walk me through what happens at between the terminal axon and neighboring dendrite, given there was a sufficient action potential.
1) Calcium (Ca+2) gates open:
-> action potential reaches end of axon
-> depolarization of membrane causes gated channels to open allowing Ca+2 to enter the cell

2) Synaptic vessels release neurotransmitter:
-> influx of Ca+2 into the terminal end causes synaptic vesicles to merge with presynaptic membrane
-> vesicles release neurotransmitters into synaptic cleft

3) Neurotransmitter binds with postsynaptic receptors (note: different proteins are used for different receptors)

4) The postsynaptic membrane is excited or inhibited:
-> depending on the kind of neurotransmitter and the kind of membrane receptors, there are two possible outcomes:

->Na+ gates open at the new neuron
-> membrane is depolarized
-> = excitatory postsynaptic potential (EPSP)
-> the reaction continues down the axon

-> if K+ gates open,
->membrane become more POLARIZED (hyperpolarized)
-> = inhibitory postsynaptic potential (IPSP)
-> become more difficult to generate a action potential on down the line.

5) The neurotransmitter is degraded and recycled.
-> neurotransmitter is broken down by enzymes

Common example:
-> neurotransmitter, acetylcholine is broken down by an enzyme
-> cholinesterase
List some common neurotransmitters:
1) Acetylcholine = commonly secreted at neuromuscular junctions, the gaps between motor neurons and muscle cells, where it stimulates the muscles to contract

2) Epinephrine, norepinephrine, dopamine, and serotonin. (from CNS)

3) GAmma aminobutyric acid (GABA) = inhibitory transmitter among neurons in the brain.
What do each of these drugs do?
A. Curare
B. Botulism toxin
C. Anti-cholinesterase
A. Curare:
-> blocks postsynaptic acetylcholine receptors
-> Result: paralysis

B. Botulism toxin:
-> prevents release of acetylcholine from the presynaptic membran
-> Result: paralysis

C. Anti-cholinesterase:
-> used as nerve gases and in the insecticide Parathion
-> inhibits the cholinesterase from breaking down acetycholine.
-> Result: no coordinated muscular contractions can take place
What the nervous systems like in each of the following phylum?

A. Protozoa
A. Protozoa (heterotrophic : like little animals)
-> no organized nervous system
-> single celled organisms may respond to
a. touch,
b. heat
c. light
d. chemicals
What the nervous systems like in each of the following phylum?

B. Cnidaria (jellyfish, corals)
-> Nerve net = simple nervous system
What the nervous systems like in each of the following phylum?
C. Annelida (Earthworms)
-> Primitive Central Nervous System:
-> ventral nerve cord
-> anterior brain of fused ganglia
-> definite nerve pathways lead from receptors to effectors.
What the nervous systems like in each of the following phylum?

D. Arthropoda (roaches, bugs)
-> brains similar to annelida
-> BUT have more specialized sense organs are present
-> ie: compound or single eyes, tympanum for detecting sound
1) Nerves are _____
2) Network of nerve fibers are called _______
3) Neuronal cell bodies often cluster together; these clusters are called ______
1) bundles of axo