Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
242 Cards in this Set
- Front
- Back
|
List the Levels of Organization from biggest to smallest
|
biosphere, ecosystems, communities, populations, organisms, organs and organ systems, tissues, cells, organelles, and molecules.
|
|
|
biosphere
|
everything; all the environments on earth that are inhabited by life.
ex: the earth |
|
|
ecosystem
|
all living things in a particular area; includes all nonliving components that life interacts with.
ex: a forest in a particular area |
|
|
communities
|
array of organisms inhabiting a particular ecosystem.
ex: diff. trees, plants, animals, in a forest |
|
|
populations
|
individuals of a specific species in a specified area
ex: a specfic tree in a community |
|
|
organisms
|
individual living things
ex: each individual tree, plant, etc.. |
|
|
organs and organ systems
|
body part consisting of two or more tissues;
team of organs that cooperate in a specific function ex: a tongue is an organ and the digestive system is and organ system because it includes the tongue, stomach, and intestines |
|
|
tissues
|
groups of similar cells
ex: skin |
|
|
cells
|
life's fundamental unit of structure and function
ex: mucscle cells *also the cell is one of the themes of bio. |
|
|
organelles
|
various functional components that make up cells
ex: chloroplasts |
|
|
molecules
|
chemical structure consisting of two or more chemical units (atoms)
ex:carbon dioxide |
|
|
reductionism
|
reducing complex systems to simpler components that are more manageable to study
|
|
|
name the eleven themes of biology
|
the cell, heritable information, emergent properties of biological systems, regulation, interaction with the environment, energy and life, unity and diversity, evolution, stucture and function, scientific inquiry, and science /technology/society
|
|
|
heritable information
|
a theme of bio.; inheritance of biological information through DNA
|
|
|
emergent properties of biological systems
|
systems properties emerge as a result of interactions among components at the lower levels.
ex: terminte mounds, cauliflower |
|
|
regulation
|
theme of biology; feedback mechanisms that regulate biological systems. Positive= a trigger to escalate something. Negative=trigger to stop something.
ex: regulation maintains body temp. |
|
|
interaction with the environment
|
theme of biology; organisms are open sytems that exchange materials and energy with their surroundings
|
|
|
energy and life
|
theme of biology; all orgs. must perform work, which requires energy. Energy flows from sunlight to producers to consumers
|
|
|
unity and diversity
|
theme of biology; despite the diversity of life, there is also much unity, such as a universal genetic code. the more closely related two species are the more characteristics they share
|
|
|
evolution
|
theme of biology; explains unity and diversity; natural selection accounts for adaptations of popultions to their environment through the reproductive success of varying individuals
|
|
|
structure and function
|
theme of biology; correlated at all levels of biological organization; way something is developed to carry out a specific function
|
|
|
scientific inquiry
|
theme of biology; process of science including observation based discovery and the testing of explanations through hypothesis-based inquiry
|
|
|
science, technology,and society
|
theme of biology; many technologies are goal-oriented applications of science
|
|
|
2 types of adaptations
|
homology - structure variation yet same bones (ex: human arm, bat wings, dolphin fin)
analogy - ex: insects and birds learning to fly |
|
|
cladogram
|
shows genetic/morphilogical/breeding similarities/potnetial
|
|
|
DNA
|
deoxyribonucleic acid; substance of genes
|
|
|
gene
|
unit of inheritance; transmit info. from parents to offspring
|
|
|
element
|
substance that cannot be broken down to other chemical substances by chemical reactions
|
|
|
compound
|
substance consisting of two or more elements combined in a fixed ratio
|
|
|
essestial elements of life
|
25 out of 92; Most common: carbon, oxygen, hydrogen, and nitrogen
|
|
|
atom
|
smallest unit of matter that still retains the properties of an element
|
|
|
Parts of an atom
|
nuetrons and protons are packed densely together to form the atomic nucleus; electrons form a cloud around the nucleus
|
|
|
nuetrons
|
part of an atom; no charge; subtract amount of protons from the atomic mass to find the number of nuetrons
|
|
|
protons
|
part of an atom; positive charge; atomic # tells the amount of protons in a certain element
|
|
|
electrons
|
part of an atom; negative charge; amount of e- and protons in an element are equal
|
|
|
atomic number
|
# of protons unique to a certain element; written as a subscript
|
|
|
isotope
|
when atom has more nuetrons than other atoms of the same element
|
|
|
energy
|
capacity to cause change
|
|
|
potential energy
|
energy that matter possesses because of its location or structure.
ex: a ball at the top of a hill; water being held back by a dam |
|
|
energy levels
|
different states of potential energy that e- have in an atom
|
|
|
e- energy level
|
correlated with its average distance from the nucleus which is represented through e- shells
|
|
|
e- configuration
|
distribution of electrons in the atoms e- shells (displayed in the periodic table of elements)
|
|
|
valence e-
|
# of e- in the outermost shell
|
|
|
valence shell
|
outermost e- shell
|
|
|
covalent bond
|
sharing of valence e- by two atoms
|
|
|
nonpolar bond
|
type of covalent bond; e- are shared equally; hydrophobic
|
|
|
polar bond
|
one atom bonded to a more electronegative atom; e- not equally shared; hydrophilic
|
|
|
Ionic bond
|
attraction between cations and anions causing a transfer in e- between atoms
|
|
|
hydrogen bond
|
forms when an H atom covalently bonded to an electronegative atom is also attracted to another electronegative atom
|
|
|
Van der Waals
|
everchanging "hot spots" of + and - charged that enable all atoms and molecules to stick to one another
|
|
|
ion
|
a charged atom
|
|
|
cation
|
+ charged ion
|
|
|
anion
|
- charged ion
|
|
|
molecule
|
2 or more atoms held together by covalent bonds
|
|
|
molecular shape and function
|
shape is determined by the positions of the atoms' orbitals; shape determines how biological molecules recognize and respond to one another specifically
|
|
|
four emergent properties of water
|
1)cohesion (and adhesion) 2)Moderation of Temperature 3)Insulation of bodies of water by floating ice 4)Solvent of life
|
|
|
Cohesion and Adhesion
|
- Emergent property of water
Cohesion: aka Tension theory (capillary action); ablitiy of water moleclues to stick to each other using hydrogen bonds; allows transport to occur(ex. water traveling from roots to leaves). Adhesion:aka Surface tension; abilty for water to stick to other things; idea that water can cling to a wall (ex. shrew walking on water) |
|
|
moderation of temperature
|
-Emergent property of water
water can absorb heat to make things cooler and release heat to make things warmer |
|
|
Insulation of Bodies of Water by Floating Ice
|
-Emergent property of water
Ice is less dense than water which allows it to float. Solid water expands due to H bonding. Floating ice insulates the water below preventing freezing and allowing life to exist. |
|
|
Solvent of Life
|
-Emergent property of water
universal solvent solvent- dissolving sgent of a solution (substance dissolved is the solute); aqueos solution- one in which water is the solvent |
|
|
kinetic energy
|
energy of motion
|
|
|
heat
|
a measure of the total amount of kinetic energy
|
|
|
temperature
|
average kinetic energy
|
|
|
calorie
|
amount of heat it takes to rise the temperature of 1g of water by 1degree Celcius
|
|
|
specific heat
|
amount of heat that must be absorbed or lost for 1g of that substance to change its temperature by 1degree Celcius
--the specific heat of water is 1cal/g/C because of the high specfic heat of h2o relative to other materials, wather will change its temp. less when it absorbs or loses a given amount of heat |
|
|
heat of vaporization
|
quanity of heat a liquid must absorb for 1g of it to be converted from the liquid to the gaseous state
|
|
|
evaporative cooling
|
ie:sweating; the surface of the liquid that remains behind cools down. occurs because the "hottest" molecules (high/greatest kinetic energy) ate the most likely to leave as gas while the low energy molecules stay and cools you down
|
|
|
hydrogen ion
|
single proton with a charge of 1+
|
|
|
hydroxide ion
|
water molecule that loses a proton; has a charge 1-
|
|
|
acid
|
substance that increases the hydrogen ion concentration of a solution
|
|
|
base
|
substance that decreases the hydrogen ion concentration of a solution
|
|
|
buffer
|
helps maintain pH; substances that minimize cahnges in concentrations of
H+ and OH- in a solution |
|
|
acid rain
|
rain with a pH lower than 5.6
|
|
|
shape of a water molecule
|
tetrahedral
|
|
|
hydrocarbons
|
organic molecules consisting of only hydrogen and carbon
|
|
|
isomer
|
variation in the architecture of organic molecules
3 types: structural, geometric, enantiomers |
|
|
structural isomer
|
difference in covalent partners
|
|
|
geometric isomer
|
same covalent partnerships, difference in arrangement around the double bond
|
|
|
enantiomer
|
molecules that are mirror images of each other; differ in spatial arrangement arounf an asymmetric carbon
|
|
|
name the six functional
|
hydroxyl, carbonyl, carboxyl, amino, sulfhydryl, and phosphate
|
|
|
hydroxyl
|
oxygen bonded to a hydrogen;-OH; alcohols
|
|
|
carbonyl
|
=O; double bonded oxygen attached to a carbon; ketone- if the carbonyl group is within the carbon skeleton, aldehyde- if the carbonly group is at the end of the carbon skeleton
|
|
|
carboxyl
|
an oxygen is double bonded to the carbon as well as a hydroxyl group
(-COOH); carboxylic acid |
|
|
amino
|
a nitrogen bonded to two hydrogens which is bonded to the carbon (-NH2); amines
|
|
|
sulfhydryl
|
sulfur bonded to a hydrogen (HS-); thiols
|
|
|
phosphate
|
a phosphorous atom bonded to four oxygens; organic phosphates
|
|
|
dehydration reaction
|
two molecules covalently bond to each other through the loss of a water molecule; also called condensation reaction
|
|
|
hydrolysis
|
reverse of dehydration reaction
|
|
|
name the macromolecules
|
carbohydrates, lipids, proteins, and nucleic acids
|
|
|
carbohydrates
|
sugars
|
|
|
lipid
|
have little to no affinity for water; made from 3 fatty chains attached to a glycerol molecule; fats
|
|
|
proteins
|
one or more polypeptides folded and coiled into specific conformations; 4 diff. stuctures
|
|
|
nucleic acids
|
exsist as polymers called polynucleotides
|
|
|
glycosidic linkage
|
covalent bond formed between two monosaccharides by dehydration reaction
|
|
|
starch
|
used for storage in plants (stored in granules called plastids)
|
|
|
two forms of starch
|
1) amylose: simple
2) amylopectin: complex |
|
|
glycogen
|
used for storage in animals; similar to amylopectin but more extensively branched
|
|
|
cellulose
|
major component of the tough walls that enclose plant cells; cannot be broken down during digestion
|
|
|
main difference between starch and cellulose
|
in starch all hydroxyl groups (-OH) are located at the same postions whereas in cellulose, the hydroxyl group can change postions; diff. glycosidic linkages
|
|
|
chitin
|
carbohydrate used by antrhopods
|
|
|
linkages within lipids
|
ester linkages
|
|
|
unsaturated fat
|
has one or more double bonds
|
|
|
saturated fat
|
all single bonds, saturated with hydrogens
|
|
|
glycerol
|
an alcohol with three carbons, each bearing a hydroxyl group
|
|
|
phospholipid
|
two fatty acids attached to glycerol along with a phosphate group; a (nonpolar/hydrophobic) fat with a (polar/hydrophilic) phospate head and some functional group
|
|
|
anthapathic molecule
|
has both a hydrophobic and hydorphilic domain
|
|
|
where is fat stored
|
adipose cells; fats can hold more thatn sugars and other carbs
|
|
|
steroids
|
lipids characterized by a carbon skeleton consisting of four fused rings
|
|
|
cholesterol
|
steriod; precursor from which all other steroids are made
|
|
|
polypeptides
|
polymers of amino acids
|
|
|
amino acids
|
organic molecules possessing both carboxyl and amino groups; 20 total; all nonpolar amino acids do not have an oxygen in the -R group, groups containing an oxygen and no charge are polar, groups containing an oxygen with a negative charge are acidic and positve charge = basic
|
|
|
levels of protein structure
|
primary, secondary, tertiary, and quaternary
|
|
|
primary structure
|
line of amino acids
|
|
|
secondary structure
|
folding of primary structure due to hydrogen bonds (alpha helix and beta pleat sheet); H bonding
|
|
|
tertiary structure
|
alpha helix and beta pleated sheets coming together through reactions within the -R groups; hydrophobic interactions contributes to tertiary structure
|
|
|
quaternary
|
overall protein structure; involves H bonds, disulfide bridge, ionic bonds hydrophobic interaction, and Van der Waals interactions
|
|
|
links amino acids
|
peptide bonds (covalent)
|
|
|
functional protein
|
one or more polypeptides precisely twisted, folded, and coiled into a molecule of unique shape
|
|
|
what determines confirmation
|
environment
|
|
|
nasent confirmation
|
properly folded protein
|
|
|
denaturation
|
changes in heat, pH, enzymatic activity, can cause changes in the proteins folding pattern
|
|
|
chaperonin
|
protein molecules that assits in the proper folding of other proteins
|
|
|
x-ray crystallography
|
used to determine a protein's 3-dimensional structure
|
|
|
nucleic acids (types)
|
deoxyribonucleic acids aka DNA and ribonucleic acids aka RNA
these molecules enable and organism to reproduce their complex components from one generation to the next |
|
|
structure of nucleotides
|
nitrogenous base, pentose sugar, and a phosphate group
|
|
|
links nucleic acids
|
phosphodiester covalent bonds
|
|
|
polynucleotides
|
consists of monomers called nucelotides
|
|
|
types of nitrogenous bases
|
purines and pyrimidines
|
|
|
purine
|
nirtogenous base; 2 rings; only exsists as DNA; adenine and guanine
|
|
|
pyrimidine
|
nitrogenous base; 3 rings; cytosine, thymine, and uracil (in RNA)
|
|
|
chagoffs rule
|
A% = T%
C% = G% |
|
|
what roles other than just being DNA do nucleotides have
|
helping in protein synthesis
|
|
|
enzymatic proteins
|
function: selective acceleration of chemical reactions
ex: digestive enzymes catalyse the hydrolysis of the polymers in food |
|
|
structural proteins
|
function: support
ex: insects and spiders use silk fibers to make their cocoons and webs; collagen and elasin rovide a fibrous framework in animal connective tissues |
|
|
storage proteins
|
function: storage of amino acids
ex: plants have storage proteins in their seeds; ; Caesin, the protein of milk, is the major source of amino acids for baby mammals |
|
|
transport proteins
|
function: transport of other substances ex: hemoglobin transports oxygen from the lungs to other parts of the body
|
|
|
hormonal proteins
|
function: coordiation of an organisms activities
ex: Insulin helps regulate the concentration of sugar in the blood of vertabrates |
|
|
receptor proteins
|
function: response of cell to chemical stimuli
ex: receptors built into the membrane of a nerve cell dectect chemical signals released by other nerve cells |
|
|
contractile and motor proteins
|
function: movement
ex: actin and myosin are responsible for the movement of muscles |
|
|
defensive proteins
|
function: protection against disease
ex: antibodies combat bacteria and viruses |
|
|
hydrophobic interactions
|
contributes to tertiary structure; occurs while a polypeptide folds into its functions conformation; when amino acids with hydrophobic (nonpolar) side chains end up clustered at the core of the protein and out of contact with the water; caused by water molecules excluding nonpolar substances and forming hydorgen bonds with each other and hydrophilic parts of the protein.
|
|
|
disulfide bridges
|
covalent bond; reinforces conformation of a protein; form where two cysteine monomers, amino acids with sulhydryl groups, are brought close together by the folding of the protein and the sulfurs from each molecule bond to each other
|
|
|
prokaryotic cells
|
bacteria and archaea; lack membrane around nucleus as well as organelles.
|
|
|
parts of a prokaryotic cell
|
plasma membrane, nucleiod, ribosomes, and cytosol
some have pili, capsule, and/or flagella |
|
|
eukaryotic cell
|
has a nucleus bounded by a membraneous nuclear envelope, and organelles.
|
|
|
plasma membrane
|
selective barriar; semipermeble; allowing passage for oxygen, carbon, and nutrients. small polar molecules w/overall nuetral charge impedes charged ions and.
|
|
|
cytosol
|
semifluid substance in which organelles are found
|
|
|
bacterical chromosome (nucleoid)
|
DNA; no nuclear envelope
|
|
|
Ribosomes
|
animals. plants, and bacteria; made up a a lg. and small subunit (ribosomal RNA and protein); cite of protein synthesis
|
|
|
nucleus
|
plants and animals; contains most of the genes in a eukaryotic cell
|
|
|
nuclear lamina
|
netlike array of potein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope
|
|
|
nucleolus
|
makes RNA along w/ proteins
|
|
|
chromosomes
|
made of chromatin (compacted DNA) located within nucleus
|
|
|
free ribosomes
|
synthesizes proteins in cytoplasm or cytosol
|
|
|
bound ribosomes
|
attached to the ER; proteins sythesized here to be secreted
|
|
|
endomembrane system
|
animals and plants; consists of plasma membrane nuclear enveloe, ER, golgi, lysosomes, and vacuoles
|
|
|
cisternae
|
membraneous tubules and sacs
|
|
|
anabolic
|
putting compounds together
|
|
|
catabolic
|
breaks down compounds
|
|
|
endoplamic reticulum (ER)
|
extensive network of membranes; continos with nuclear envelope
|
|
|
smooth ER
|
makes oils, phopholipids, steroids; detoxifies drugsl plentiful in liverl stores calcium ions
|
|
|
rough ER
|
has ribosomes; makes proteins and transports them to Golgi bodies
|
|
|
golgo apparatus
|
modifies protein products; ships them off to other destinations
|
|
|
autophagy
|
cell recycles its own materials; lysosome breaking down damaged organelle
|
|
|
cis face
|
part of the golgi; next by the ER; recieves proteins
|
|
|
trans face
|
part of the golgi; where protein is packaged out of golgi; gives rise to vesicles
|
|
|
transport vesicles
|
vesicles in transit from one part of cell to another
|
|
|
glycoproteins
|
proteins that have carbohydrate covalently bonded to them
|
|
|
lysosomes
|
animals; digest macromolecules by phagocytosis; optimal pH of 5; maintains pH of cell by taking in excess hydrogen cations; burts to kill cell
|
|
|
phagocytosis
|
lysosomes digest (hydrolyze) materials taken into cell and recycle intracellular materials
|
|
|
food vacuoles
|
fuse with lysosomes to break down macromolecules, formed by phagocytosis
|
|
|
contractile vacuoles
|
pumps out excess H2O to maintain salt concentration
|
|
|
central vacuoles
|
plants; energy storage, plant growth (enlarges when water is absorbed) becoming turgid
|
|
|
turgid
|
when a plant is filled with H2O
|
|
|
tonoplast
|
plants; selective membrane; encloses the cetral vacuole (which contains cell sap);
|
|
|
mitochondria
|
animals and plants; location of cellular respiration (contains DNA and ribosomes)
|
|
|
Inner membrane (cristae)
|
phospholipid layer of mitochondria; folds in on itself giving more surface areaand increasing energy yield
|
|
|
mitochondrial matrix
|
contains enzymes necessary to catalize reactions of Krebs cycle
|
|
|
chloroplasts
|
plants; energy processing; two membranes; has ribosomes and DNA; semiatonomous; contains pigment chlorophyll; related to plastids (granuels w/in cellular structures which store starch)
|
|
|
thylakoid membrane
|
location of chlorophyll pigment; where light synthesis begins
|
|
|
stroma
|
liquid in chloroplasts, has DNA and ribosomes
|
|
|
amyloplasts
|
colorless; stores amylase
|
|
|
chromoplasts
|
have pigment for fruit and flowers
|
|
|
granum
|
stack of thylakoids
|
|
|
peroxisomes
|
related to respiration; breaksdown fatty acids; imports proteins from cytosol; bound by single membrane; transfers H2O to create H2O2; detoxifies alcohol; grows by collecting proteins, cytosol, and lipids
|
|
|
cytoskeleton
|
animals and plants; regulates biochemical activities; network inside a cell for substances to travel; mechanical and structural support; involved in motility through interaction w/motor proteins.
3 components: microtubles, microfilaments, and intermediate filaments |
|
|
microtubles
|
pt, of cytoskeleton; thickest fibers; found in cytoplasm; hollow rods; walls are made from tubulin; grow from centrosomes; maintain cell shape through compression resisting girders
|
|
|
centrosomes
|
microtubule organizing center
|
|
|
centrioles
|
animals; where microtubules are assembled
|
|
|
cilia/flagella
|
specialized arrangements (doublets) of microtubules; locomoter appendeges; flagella are longer and move in the same direction of the axis; cillia are shorter and move perpendicular to the axis
|
|
|
microfilaments (actin)
|
thinnest; responsible of muscle cell contraction, involves pushing actin towards myosin; maintains shape through tension baring elements
|
|
|
intermediate filaments
|
proteins put in cables (ie: carotin); more permanent (microtubules/filaments can break apart and chang as cell changes); important in maintaining shape of cell and repositionign organelles
|
|
|
dynein
|
motor protein b/t doublets made of several polypeptides (which hold doublets together)
|
|
|
Integrins
|
proteins built into plasma membrane
|
|
|
cell wall
|
bacteria and plants; thick for protection; prevents excessive uptake of H2O; composed of cellulose; thin primary wall, midddle lamena (rich in the polysacch. pectin);
|
|
|
how does the cell wall harden
|
1- secreting hardening substances in the middle layer. 2- adding a secondary wall
|
|
|
extracellular matrix (ECM)
|
mainly glycoproteins; collagen; forms strong fibers outside cell; proteins called integrins help pass down signals; can make a change
|
|
|
Plasmodesmata
|
plants; intrecellular junction; perforated channels within cell wallsl cytosol passes through and connects the chemical enbironment of adjacent cells, unifying plant into one living continuum. H2O and small solutes can pass freely from cell to cell and specific proteins and macromolecules reach plasmodesmata by moving along fibers of the cytoskeleton
|
|
|
tight junctions
|
animals;intracellular junction; prevent leakage of extracellular fluid across a layer of epithelial cells; caused by membranes of neighboring cells packed tightly and bound by specific proteins
|
|
|
desmosomes
|
animals; intracellular junction; aka anchoring junction; fasten cells together into strong sheets; intermidiate filaments make of sturdy keratin proteins anchor desmosomes in the cytoplasm
|
|
|
gap junctions
|
animals; intracellular junction; aka comunicating junction; provides cytoplasmic channels from one cell to adjacent cell; consist of special membrane proteins that surround pore through which ions, sugars, amino acids, and other small molecules may pass; necessary for communication between cells
|
|
|
amphipathic molecule
|
phospholipid; has both hydrophobic and hydrophilic regions
|
|
|
6 major functions of membrane proteins
|
transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining, and attachment to the cytoskeleton and extracellular matrix (ECM)
|
|
|
trasport
|
a protein ca have a hydrophilic channed across the membrane that is selective for a particular solute. or protein can shuttle proteins from one side to another by changing shape. (sometimes ATP is hydrolyzed for energy) ;can create a hydrophilic tunnel
|
|
|
enzymatic activity
|
several enzymes in a membrane are organized as a team that carries out sequential steps of a metabolic pathway
|
|
|
signal transduction
|
protein may have a binding site (requiring a certain hormone etc) and the signal can cause a conformational change in the protein (receptor) which relays the message to the cell
|
|
|
cell-cell recognition
|
some glyconproteins serve as identification tags that are specifically recognized by other cells; cells ability to recognize one type of neighboring cell from another
|
|
|
intercellular joining
|
membrane proteins of adjacent cells may hook together in various kinds of junctions
|
|
|
attachment to the cytoskeleton and extracellular matrix (ECM)
|
microfilaments or other elements of the cytodkeleton may be bonded to membrane proteins which can coordinate extracellular and intracellular changes
|
|
|
permeability of the lipid bilayer
|
hydrophobic (nonpolar) molecules (ie: hydrocarbons, CO2, and O2) can dissolve in the loped bilayer and cross it with ease. However, the hydrophobic core of the membrane impedes the direct passage of ions and polar molecules (hydrophilic) through the membrane
|
|
|
aquaporins
|
channel proteins that help with the passage of H2O through the membrane
|
|
|
Transport types
|
diffusion, passive, and active
|
|
|
diffusion
|
substance moves from an area of higher concentration to one of less concentration
|
|
|
osmosis
|
H2O moving from an area with lower solute concentration to one with higher solute concentration
|
|
|
passive transport
|
diffusion of a substance across a biological membrane; cell doesn't have to expend energy
|
|
|
tonocity
|
ability of a solution to cause a cell to gain or lose H2O
|
|
|
isotonic
|
concentrations within and outside the cell are the same
|
|
|
hypertonic
|
when the environment has a greater concentration of solute than the cell the environment is hypertonic to the cell and H2O leaves the cell
|
|
|
hypotonic
|
when the environment has lower solute concentration than the cell the environment is hypotonic to the cell and water wants to come inside the cell
|
|
|
osmoregulation
|
control of water balance
|
|
|
describe animal and plant cells when placed in a hypotonic solution
|
animal - lysed
plant - turgid |
|
|
describe animal and plant cells when placed in an isotonic solution
|
animal - normal
plant - flaccid |
|
|
describe animal and plant cells when placed in a hypertonic solution
|
animal - shriveled
plant - plasmolyzed |
|
|
plasmolysis
|
plant loses so much water that it wilts; plasma membrane of plant cells pulls away form the cell wall
|
|
|
facilitated diffusion
|
molecules diffuse passively with the help of transport proteins
|
|
|
ion channels
|
gated; stimulus (electrical or chemical) causes them to open/close
|
|
|
active transport
|
uses energy to go against gradient
|
|
|
sodium potassium pump
|
ex of active transport; uses 3 Na ions to facilitate 2 K ions; requires phosphorylation of ATP
|
|
|
voltage
|
electrical potential energy
|
|
|
membrane potential
|
voltage across membrane; avg = -50 to -200 millivolts
|
|
|
electrochemical gradient
|
combination of chemical and electrical forces acting on an ion
|
|
|
electrogenic pump
|
transport protein that generates voltage across membrane
|
|
|
proton pump
|
actively transports H+ ions out of cel
|
|
|
cotransport
|
when an ATP powered pump indirectly drives the active transport of solutes other than the specific solute its meant to transport
|
|
|
ligand
|
general term for any molecule that binds specifically to a receptor site of other molecules
|
|
|
exocytosis
|
when the cell secretes macromolecules by the fusion of vesicles with the plasma membrane
|
|
|
endocytosis
|
when the cell takes macromolecules and particulate matter by forming new vesicles from the plasma membrane
|
|
|
types of endocytosis
|
phagocytosis, pinocytosis, and receptor mediated endocytosis
|
|
|
phagocytosis
|
cell engulfs particle, create vacuole which fuses with lysosome containing hydrolytic enzymes
|
|
|
pinocytosis
|
cell collects small amounts of extracellular fluid, tiny vesicles transport the molecules dissolved in the fluid
|
|
|
receptor-mediated endocytosis
|
enables the cell to aquire bulk quantities of specific substances;extracellular substances bind to specific receptors embedded in the protein and exposed to the extracellular fluid. a coated pit forms a vesicle containing the substance and after ingestion, the receptors are recycled back to the membrance by vesicles
|
|
|
what are the 7 properties of life
|
order, evolutionary adaptation, response to the environment, regulation, energy processing, growth and development, and reproduction
|
