Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/193

Click to flip

193 Cards in this Set

  • Front
  • Back
What is discovery science?
Discovering of new info based on what we can record, measure, or observe
What are two examples of discovery science?
1) descriptive anatomy - not asking a question, just describing what you see, feel, etc.
2) animal behavior (observing)
What is inductive reasoning? What is an example?
Using specific observations to form general theories (descriptive)

*Specific observations and measurements LEAD TO general theories*

ex: Cell Theory - all organisms are made of cells (centuries of observations by scientists)
What is hypothesis-driven science?
Scientific method - deductive reasoning - discovery by starting with a specific question; use controlled experiments to come up with a tentative answer
What are the steps of the scientific method?
1) Observations
2) Question
3) Hypothesis - tentative answer to our question (should test only one at a time)
4) Prediction - "if, then" statement
5) Perform a controlled experiment; experimental group and a control group
6) Results
7) Conclusion - do the results support the hypothesis?
What was the example used in class to illustrate the scientific method?
Mimicry example:

1) Observations: Zebra spiders wave their legs around competing zebra spiders; snowberry flies wave their wings when approached by zebra spiders

2) Question: What is the function of the fly's wing markings?

3) Hypothesis: The markings increase survival causing the spider to flee without pouncing.

4) Prediction: If the fly's wings are masked then the spiders will pounce upon the masked flies more.

5) Controlled experiment: a) experimental group - dyed wing flies, b) control group - normal flies, c) measure - pounce rates

6) Results: a) experimental group - 38% pounce rate, b) control group - 20% pounce rate

7) Conclusion - Data support hypothesis
What is deductive reasoning?
Reasoning from general theories to account for specific experimental results

*General theories ACCOUNT FOR specific observations and measurements in experimental results*
What is a scientific theory?
A hypothesis that has not been disproved after years of RIGOROUS testing
What is an organic compound?
Contains carbon (which can make 4 bonds), usually limited to hydrogen and oxygen (and sometimes nitrogen)
What are the 4 major macromolecules in the cell?
1) Carbohydrates
2) Lipids
3) Proteins
4) Nucleic acids (DNA and RNA)

*All 4 are organic compounds*
What do macromolecules consist of?
Monomers which form polymers when they are put together
What is a condensation reaction? What is another name for a condensation reaction?
Also called dehydration synthesis - occurs when monomers are joined and water is lost to the environment
What is hydrolysis?
Occurs when polymers are broken and water is added back into the environment
What does monosaccharide literally mean?
"One sugar"
What is the chemical formula for carbohydrate monomers?
Some multiple of CH2O
What type of monomer is glucose? What is its chemical formula? What is its function?
Carbohydrate - C6H12O6 - main fuel for our cells (source of energy)
What type of monomer is fructose? What is its chemical formula? What is its function?
Carbohydrate - C6H12O6 - corn syrup
What type of monomer is galactose? What is its chemical formula? What is its function?
Carbohydrate - C6H12O6 - sugar found in milk
What are disaccharides?
Two simple sugars joined by a condensation reaction - carbohydrates
What is lactose?
Carbohydrate - galactose + glucose (milk)
What is sucrose?
Carbohydrate - glucose + fructose (table sugar)
What is maltose?
Carbohydrate - glucose + glucose (malt sugar - in beer)
What ending should indicate a sugar?
-ose
Does the body process artificial sweetners as sugar?
No - this is why people use artificial sweetners for various reasons such as dieting or as a replacement for sugar for diabetics
What are some examples of artificial sweetners?
1) Sucralose - Splenda, modified version of sucrose
2) Nutrasweet - not a sugar but a dipeptide
What are polysaccarides and what does it mean?
Complex carbohydrates - means "many sugars"
What are 4 examples of polysaccarides?
1) Starch
2) Glycogen
3) Cellulose
4) Chitin
What is the function of starch?
Glucose storage molecule for plants (amylose)

- present in potatoes
What is the function of glycogen?
Glucose storage molecule in animals

- found in liver and muscles
What is the function of cellulose?
Structural molecule in plants: "fiber," hydrogen bonding, tough, resistant to hydrolysis, and insoluble

- animals cannot hydrolyze (just passes through)
What is the function of chitin?
Structural molecule in animals, nitrogen present in this molecule, not in humans, found in many hard shells of animals (exoskeleton)

- example is in the outer shell of a crab
What is a common trait of lipids?
All are hydrophobic ("water fearing")
What is triglyceride?
A type of "fat," energy storage molecule in plants and animals
What are some characteristics of triglycerides?
1) Monomers - glycerol + fatty acids
2) Polymer - 1 glycerol + 3 fatty acids
3) Unsaturated fats - many come from plants (vegetable oil, olive oil), tend to be liquid at room temperature, double bonds so that the fatty acids do not pack tightly
4) Saturated fats - many come from animals (butter, lard), tend to be solid at room temperature, do not have double bonds in the fatty acids which causes them to pack tighter together
5) Two times as much energy as carbohydrates
What are phospholipids?
A major component of cell membranes
What are some characterisitics of phospholipids?
1) Monomers - hydrophilic (phosphorous) head + 2 fatty acids
2) Hydrophobic tails + hydrophilic ("water loving") heads = amphiphilic
What does amphiphilic mean?
"Both" (-amp) water loving and water fearing
What are some characteristics of steroids?
1) Monomers - 4 carbon rings (no fatty acids)
2)Hormones and cholesterol are 2 examples of steroids

- Testerone and estrogen are both examples of hormones
- Cholestrol is an important component of the cell membrane
What are some characterisitics of waxes?
1) Monomers - 1 long fatty acid + OH group or carbon ring
2) More hydrophobic than lipids
3) Some examples: plants have a natural protective layering of wax to maintain moisture, apples have wax put on the skin so that they stay fresher longer
How many different amino acids are there?
20
Out of the 20 different types of amino acids, how many are "essential"?
9 (generally found in animals)
What do amino acids consist of?
Amino group, carboxyl group, and "R" group (each amino acid is different in "R" group)
Amino acids have different what?
Chemical properties (ex: charged, hydrophobic, "bulky", etc.)
What are amino acids?
Proteins
What are polypeptides?
"Many" amino acids bonded covalently through "peptide" bonds
What is the 1 degree protein structure?
Primary structure - amino acid sequence
What is the 2 degree protein structure?
Secondary structure - alpha-helix (coil) or beta-pleated sheets (accordian) held together by hydrogen bonds between carboxyl of one amino acid and amino group of another
What is the 3 degree protein structure?
Tertiary structures (3D) - 3 dimensial shape that is held together by the unique "R" group interactions
What is the 4 degree protein structure?
Quaternary structure - not all proteins have 4 degree structure, only proteins consisting of 2 or more interacting polypeptides have a quaternary
Structure and what are linked in proteins?
Function
What causes a mutation in DNA?
A change in protein structure (ex: mutation in hemoglobin gene causes sickle cell disease)

**DNA codes for protein**
What are disease causing proteins called?
Prions
What is a prion?
A misfolded protein in the brain that is resistant to degradation
How do prions affect other proteins?
They convert normally folded proteins into prions
What are prions affect on their host?
The cells (neurons) become clogged which leads to cell death
What are the 7 functions of proteins?
1) structural
2) contractile
3) storage
4) defensive
5) transport
6) signaling
7) enzymes

**Not all proteins are enzymes**
What does DNA stand for?
Deoxyribonucleic acid
What are the monomers of DNA called and what do they consist of?
Nucleotides - they consist of:
- deoxyribose (15 carbon sugar)
- phosphate group (negatively charged)
- nitrogenous base (4 kinds - A, T, C, G)
What is a DNA polymer called and what is it?
Polynucleotide - nucleotides linked together
What is a double helix structure?
Two polypeptides in a helix - if A is on one side then T is on the other; if G is on one side then C is on the other
What does RNA stand for?
Ribonucleic acid
What are the monomers of RNA called and what do they consist of?
Nucleotides - they consist of ribose, phosphate, and nitrogen bases (A, U, G, C)
What is the structure of RNA?
Single stranded
The cell is the smallest unit with the properties of life. What are these properties?
Cells can metabolize (build/break macromolecules), they can respond to the environment, and they can grow and reproduce
What are the 3 features that all cells have in common?
1) Plasma membrane (separates cell from environment; regulates transport; receives signals)
2) Hereditary material (DNA; can be copied and read)
3) Cytoplasm (water based semi-fluid; holds all organelles and cytoskeleton)
What are the two types of cells in nature?
- Prokaryotes
- Eukaryotes
What does prokaryote mean?
"Before kernel" - does not have a nucleus (still has DNA but it is not enclosed in cytoplasm)
What does eukaryote mean?
"True kernel" - a nucleus is present (animal and plant cells)
What is cell size constrained by?
Surface area - as the cell gets larger the surface area decreases

**Smaller cells have more surface area, relative to size, than larger cells**
Who was one of the first scientists to look at a biological specimen under a microscope in the early 1600s?
Galeileo Galiliei
What is the structure of smooth endoplasmic reticulum(ER)?
Continuous with RER membrane but with no ribosomes
What is the function of smooth ER?
Has enzymes within it, synthesizes lipids, makes hormones, makes new phospholipid membrane, detoxifies
What are the structure of golgi bodies?
Flattened sacs; NOT continuous with ER
What are the function of golgi bodies?
Chemically modify lipids and proteins; shipping and receiving
What is the structure of rough endoplasmic reticulum (RER)?
RER membrane is continuous with nuclear membrane; stacked, flattened sacs with ribosomes attached
What is the function of the RER?
To aid in folding polypeptides that will be secreted from the cell
What is the structure of a lysosome?
A membrane enclosed vesicle, buds from Golgi; contains digestive enzymes
What is the function of a lysosome?
To digest macromolecules, old organelles, and foreign matter
What is the structure of the central vacuole?
A large storage vesicle (membrance enclosed) in plants (not animals!)
What is the function of the central vacuole?
Stores ions, amino acids, and sugars
What are mitochondria and where are they found?
Energy producing organelles that are found in ALL eukaryotic cells
What is the function of mitochondria?
Transfer the energy in carbohydrates to cellular energy (ATP) in the presence of oxygen
What is the structure of mitochondria?
There is an inner and an outer membrane, intermembrane space (b/w inner and outer); the inner membrane is folded (called cristae) for extra space (*the more enzymes you can fit, the more energy you can produce*)
What are chloroplasts and where are they found?
Energy producing organelles that are found in plant cells and some protists
What is the function of chloroplasts?
To trap sunlight with photosynthetic pigments - carbs
What is the structure of chloroplasts?
Outer and inner membrane (intermembrane is b/w them); discs outside inner membrane are called thylakoid
What is thylakoid?
A membrane that captures sunlight; discs located outside the inner membrane of chloroplasts
What is the cytoskeleton?
An interconnected network of fibers in the cytoplasm
What are the 3 parts of the cytoskeleton?
Microtubules, microfilaments, intermediate filaments
What is the structure of microtubules?
Long, hollow cylinders of tubulin (protein) subunits - the thickest
What is the function of microtubules?
"Tracks" for chromosomes and organelles
Can microtubules assemble and disassemble?
Yes - they are being built in one direction and being taken away in another (dynamic fibers)
What is the structure of microfilaments?
Two coiled polypeptide chains of actin (protein) subunits - the thinnest
What is the function of microfilaments?
Cell movement, pseudopods, cell pinching during cell division
Can microfilaments assemble and disassemble?
Yes - dynamic fibers
What is the structure of intermediate filaments?
Ropelike, made of various fibrous proteins, intermediate thickness
What is the function of intermediate filaments?
Support for tension, also cages the nucleus
Can intermediate filaments assemble and disassemble?
No - holds cytoplasm as a firm structure
How are flagella and cilia arranged?
9 + 2 doublet arrangement of microtubules

- flagella are longer than cilia; there are many more cilia per cell
The base in the cyotoplasm equals what?
9 triplets of microtubules
What is dynein?
Protein with "arms"; can change so that the cell moves
What are pseudopods?
Temporary lobes that project from the cell (think of an amoeba)
What are the 2 plasma membrane extensions?
1) flagella and cilia
2) pseudopods
What do carbohydrate frameworks provide mechanical support in?
Protists, plants, fungi
What kind of cell wall do plants have?
1 degree cellulose wall and a 2 degree cell wall made of lignin
What is external to the plasma membrane of animal cells?
Extra cellular matrix (ECM) - made up of various secretions from cells
What is the name of the pores in the cell walls of plants that allow communication between neighboring cells?
Plasmodesmata (pass macromolecules back and forth)
What are the 3 types of junctions that animal cells display?
1) gap (communicating) - similar to plasmodesmata in plants
2) tight junctions - form waterproof sheets (like caulking)
3) adhering junction - helps cells anchor next to each other ("spot welds")
What is the structure of a membrane?
Phospholipid bi-layer
What is the function of a membrane?
It is selectively permeable - allows some substances to cross, but not all
What can freely cross through a membrane?
Oxygen and carbon dioxide, some water molecues, small non-polar (non-charged) molecules
What can cross through a membrane with help from transporter proteins?
Glucose, large polar (charged) molecules, ions, water molecules
What is passive transport?
Process that does not require the cell to use energy
What is diffusion?
When particles spontaneously move to areas of lower concentration
What is a concentration gradient?
Particles move from high to low concentrations
What is dynamic equilibrium?
The concentration is equal on both sides of the membrane; molecules can still move but there is a zero net change
What is another name for diffusion of water in a cell?
Osmosis
What does hypotonic mean?
Low concentration of solutes
What does hypertonic mean?
High concentration of solutes
What does isotonic mean?
Equal concentration of solutes on both sides
What does osmoregulation mean?
The control of osmosis in an organism
How is facilitated diffusion different from simple diffusion?
It uses transporter proteins in the membrane (channels)
How is facilitated diffusion similar to simple diffusion?
The molecules are following the concentration gradient (high to low)
What is an example of facilitated diffusion?
Glucose
How do molecules move in active transport?
They move against the concentration gradient (low to high)
What does active transport require?
Energy b/c this is "work" for the cell and also a transporter protein
What is an example of active transport?
Calcium pump
What is exocytosis and what is it an example of?
"Exo" means "out" - an example of bulk transport
What is endocytosis and what is it an example of?
"Endo" means "in" - an example of bulk transport (the membrane may fold inward, trapping material from the outside)
What is phagocytosis?
Part of endocytosis - "cellular eating" - bringing large bulky items in (ex: amoeba taking in a bacteria)
What is pinocytosis?
Part of endocytosis - "cellular drinking" - bringing in small droplets
What is receptor-mediated endocytosis?
Highly specific; a pit forms with receptors to bind specific molecules
What are most enzymes?
Proteins - catalysts (increases the rate of a reaction)
If a word ends in "ase" what should you think of?
Enzymes - think of a protein BUT not all proteins are enzymes
What is a protease?
Digests proteins
What is a DNA polymerase?
Builds polymers of DNA
What is lactase?
Protein that breaks down lactose
How do enzymes increase the rate of a reaction?
They lower the Energy of Activation (EA) barrier

EA = minimum amount of energy that is needed to start a reaction (molecules being aligned properly for bonds to break)
What are the steps that describe the process of a substrate to an enzyme to a product?
1) empty enzyme
2) substrate binds the active site of an enzyme
3) substrate is brought to "transition" state" (molecule is aligned such that bonds are ready to break)
4) bonds break and product forms
5) product is released and the enzyme is unchanged and can repeat the process
During a given time frame enzymes can be what?
Saturated - enzymes reach a limit eventually, they can only do so much work
What are the 3 types of enzyme inhibitors?
1) competitive inhibitor, 2) non-competitive inhibitor, 3) feedback inhibition
What is a competitive inhibitor?
Competes for the active site (where the substrate binds) so the substrate can't bind (causes less product to be made)
What is a non-competitive (allosteric) inhibitor?
Binds to a site on enzyme other than active site but causes a shape change in the active site
What is feedback inhibition?
When the product of the reaction is also the inhibitor
What are the 3 factors that affect enzyme driven reactions?
1) temperature, 2) pH (acid or base), 3) salt concentration
What is an endergonic reaction? What is an example of one?
Ender means "energy in" - products have more energy than the reactants

ex: photosynthesis
What is an exergonic reaction? What is an example of one?
Exer means "energy out" - reactants have more energy than the products

ex: combustion of glucose
How does energy release in cells occur?
In many small steps (store energy in covalent bonds)
What is cellular metabolism?
Sum of endergonic and exergonic reactions in the cell
What is ATP?
Energy currency of cells
What is the function of ATP?
Spent during endergonic reactions and gained during exergonic reactions
What is the structure of ATP?
Adenine - ribose - phosphate
How does ATP provide energy?
ATP can donate the last phosphate to a protein which is then primed to do "work"
ADP + P ->
ATP (cell cycles through this)
What are oxidation-reduction (redox) reactions?
When electrons are transferred between molecules
If the donor molecule loses one or more electrons it has been what?
Oxidized (LEO)
If the acceptor molecule gains one more electrons it has been what?
Reduced (RIG)
What is ATP synthase?
Membrane-bound active transport protein that acts as an enzyme of ATP formation
What are the three series of reactions required for aerobic respiration?
1) Glycolysis, 2) Krebs cycle, 3) Electron transfer phosphorylation
What is the summary of the aerboic respiration (the chemical formula)?
C6H12O6 + 6O2 -> 6CO2 + 6H2O + 36ATP
What is another name for anaerobic respiration?
Alcoholic or lactate fermentation
Where does anaerobic respiration (or fermentation) occur?
In the cytoplasm
Where does glycolysis occur within the cell?
In the cytoplasm
What are the end products of glycolysis?
2 pyruvates, 2 ATP, and 2 NADH
Where does the second stage of aerobic respiration occur?
In the mitochondrial matrix (inner compartment)
What are the two main reactions within the second stage of aerobic respiration?
Acetyl-CoA formation and the Krebs Cycle
What are the end products of the second stage of aerobic respiration?
8 NADH, 2 ATP, 2 FADH2, 6 CO2
What is the third stage of aerobic respiration? Where does it occur?
Electron transfer phosphorylation - occurs in the inner membrane of the mitochondria
How many ATPs does electron transfer yield?
36
How many ATPs does glycolysis yield?
2
How many ATPs does the Krebs Cycle yield?
2 ATPs
What is the total amount of ATPs generated per glucose molecule in aerobic respiration?
36
When energy is transferred from glucose to ATP in the presence of oxygen, the efficiency is about what?
40%
When does anaerobic respiration operate?
When oxygen is absent or very limited
What is the efficiency of anaerobic respiration?
2%
Fermentation is a way of generating more of what?
NAD+ (oxidized form)
In alcoholic fermentation 2 pyruvates yield what?
2 ethanol, 2 CO2, and 2NAD+ (yeast uses this)
In lactate fermentation 2 pyruvates yield what?
2 lactate and NAD+
Who uses photosynthesis?
Photosynthetic autotrophs ("self feeders") - plants, some bacteria, some protists
What is the chemical formula of photosynthesis?
6CO2 + 6H2O + light energy -> 6O2 + C6H12O6
What are the 3 compartments of the chloroplast?
1) intermembrane space, 2) stroma (inside the intermembrane space), 3) thylakoids
What is a pigment?
A molecule that absorbs photons of a particular wavelength?
What is chlorophyll a? What is chlorophyll b?
Chlorophyll a is a major pigment; chlorophyll b is an accessory pigment (does not participate directly)
Are the shortest or longest wavelengths most energetic?
Shortest wavelengths are most energetic (purple/blue); longest wavelenghts are least energetic (red)
What are photosystems?
Accessory ("antennae") molecules - help absorb light energy and transfer it to reaction center
What does the reaction center of a photosystem consist of?
A single molecule of chlorophyll a and a primary electron acceptor
What is a photon?
A packet or fixed quantity of light
Where does the light dependent (or Hill reaction) of photosynthesis occur?
Thylakoid membrane
What is a summary of the light dependent reaction?
Light energy -> useable cellular energy (ATP); also makes NADPH and O2
What are the key steps of the light dependent reaction?
1) light absorption and electron excitement in Photosystem II
2) series of redox reactions in electron transfer chain in thylakoid membrane
3) facilitated diffusion of H+ into stroma via ATP synthase
4) transfer and re-excitement of electrons in Photosystem I
5) a series of redox reactions in ETC
6) electron replacement for Photosystem II
What is another name for the light independent reaction of photosynthesis?
Calvin Benson Cycle
Where does the Calvin Benson Cycle occur?
In the stroma
What is a summary of the Calvin Benson Cycle?
CO2 + ATP + NADPH -> glucose (step where we make the sugar)