Terms : Hide Images
| 1120683291 | photophores | light-producing organs which emit a soft glow that matches the light filtering down from above | 0 | |
| 1120683292 | counter-illumination | what photophores use to blend in with light from above | 1 | |
| 1120683293 | bioluminescence | Emission of light by a living organism (i.e. algae) -90% of deep-sea marine life produce this | 2 | |
| 1120683294 | fluid mosaic | description of membrane structure, depicting cellular membrane as a mosaic of diverse protein molecules embedded in a fluid bilayer of phospholipids | 3 | |
| 1120683295 | selective permeability | a property of cell membranes; allows some substances to cross more easily than others | 4 | |
| 1120683296 | thermal motion (heat) | energy used for random movement of molecules | 5 | |
| 1120683297 | diffusion | tendency for particles of any kind to spread out evenly in an available space | 6 | |
| 1120683298 | concentration gradient | a region along which the density of a chemical substance increases or decreases | 7 | |
| 1120683299 | equilibrium | when solutions on both sides of a concentration gradient have equal concentration | 8 | |
| 1120683300 | passive transport | diffusion of a substance across a biological membrane, with no expenditure of energy | 9 | |
| 1120683301 | osmosis | diffusion of water across a selectively permeable membrane | 10 | |
| 1120683302 | tonicity | the ability of a solution surrounding a cell to cause that cell to gain or lose water | 11 | |
| 1120683303 | isotonic | solution that has no effect on passage of water into or out of the cell -cell's volume remains constant -characteristic of IV fluids to blood cells | 12 | |
| 1120683304 | flaccid | isotonic plant cells | 13 | |
| 1120683305 | hypotonic | a solution with a solute concentration lower than that of the cell | 14 | |
| 1120683306 | lysed | in a hypotonic animal cell, when the cell gains water and bursts | 15 | |
| 1120683307 | turgid | a hypotonic plant cell; healthy state for most plant cells | 16 | |
| 1120683308 | hypertonic | a solution with a higher solute concentration -cell shrivels and can die from water loss | 17 | |
| 1120683309 | crenate | hypertonic animal cell | 18 | |
| 1120683310 | plasmolyzed | hypertonic plant cell | 19 | |
| 1120683311 | osmoregulation | control of water balance in a cell | 20 | |
| 1120683312 | facilitated diffusion | passage of a substance through a specific transport protein across a biological membrane down its concentration gradient -type of passive transport | 21 | |
| 1120683313 | aquaporin | transport protein that facilitates diffusion of water across membrane (osmosis) -a single one allows entry or exit of up to 3 billion water molecules per second | 22 | |
| 1120683314 | active transport | cell must expend energy to move a solute against its concentration gradient -energy supplied by ATP | 23 | |
| 1120683315 | exocytosis | helps cells export bulky materials like proteins or polysaccharides | 24 | |
| 1120683316 | endocytosis | transport process that is the opposite of exocytosis; cells take in large molecules -depression in plasma membrane pinches in and forms vesicle enclosing material that had been outside cell | 25 | |
| 1120683317 | phagocytosis | cellular "eating"; a cell engulfs macromolecules, other cells, or particles into its cytoplasm | 26 | |
| 1120683318 | pseudopodia | used in phagocytosis; wrap around particle packaging it with a membrane-enclosed sac large enough to be called a vacuole, then fuses with a lysosome, who hydrolytic enzymes digest contents of vacuole | 27 | |
| 1120683319 | pinocytosis | cellular "drinking"; cell takes fluid and dissolved solutes into small membranous vesicles -NOT SPECIFIC-takes in any and all solutes dissolved in droplets | 28 | |
| 1120683320 | receptor-mediated endocytosis | movement of specific molecules into cell by inward budding of membranous vesicles, which contain proteins with receptor sites specific to molecules being taken in -HIGHLY SELECTIVE -plasma membrane indents to form coated pit, whose receptor proteins pick up particular molecules from surroundings | 29 | |
| 1120683321 | low-density lipoproteins (LDLs) | lipoproteins containing a moderate amount of protein and a large amount of cholesterol; "bad" cholesterol; bind to receptor proteins and enter cells by endocytosis | 30 | |
| 1120683322 | familial hypercholesterolemia | LDL receptor proteins are defective and cholesterol accumulates to high levels in blood, leading to athersclerosis | 31 | |
| 1120683323 | energy | capacity to cause change or to perform work | 32 | |
| 1120683324 | kinetic energy | energy of motion | 33 | |
| 1120683325 | heat (thermal energy) | type of kinetic energy associated with the random movement of atoms or molecules | 34 | |
| 1120683326 | potential energy | energy that matter possesses as a result of its location or structure | 35 | |
| 1120683327 | chemical energy | potential energy available for release in chemical reaction -most important type of energy for living organisms | 36 | |
| 1120683328 | thermodynamics | study of energy transformations that occurs in a collection of matter -system is matter under study; rest of universe is the surroundings | 37 | |
| 1120683329 | first law of thermodynamics | also known as law of energy conservation, states that energy in the universe is constant; can't be created or destroyed | 38 | |
| 1120683330 | entropy | measure of disorder or randomness -more random=greater entropy | 39 | |
| 1120683331 | second law of thermodynamics | energy conversions increase entropy (disorder) of the universe | 40 | |
| 1120683332 | cellular respiration | chemical energy stored in organic molecules is converted to a form that the cell can use to perform work -waste products are mostly CO2 and water -cells convert 34% of chemical energy in fuel to energy for cellular work vs. 25% for a car -other 66% of chemical energy generates heat | 41 | |
| 1120683333 | exergonic reaction | chemical reaction that releases energy -reaction releases to surroundings amount of energy equal to difference in potential energy between reactants and products | 42 | |
| 1120683334 | endergonic reactions | energy-requiring chemical reactions that yield products rich in potential energy | 43 | |
| 1120683335 | metabolism | total of an organism's chemical reactions -road map of thousands of chemical reactions arranged as intersecting metabolic pathways | 44 | |
| 1120683336 | metabolic pathway | series of chemical reactions that either builds a complex molecule or breaks down a complex molecule into simpler compounds | 45 | |
| 1120683337 | energy coupling | use of energy released from exergonic reactions to drive essential endergonic reactions | 46 | |
| 1120683338 | ATP | adenosine triphosphate, the main energy source for cells | 47 | |
| 1120683339 | adenosine | consists of adenine, nitrogenous base, and ribose | 48 | |
| 1120683340 | triphosphate | chain of 3 negatively charged phosphate groups -bonds are unstable and can be readily broken by hydrolysis | 49 | |
| 1120683341 | Phosphorylation | The transfer of a phosphate group, usually from ATP, to a molecule -endergonic | 50 | |
| 1120683342 | Chemical work | Phosphorylation of reactants provides energy to drive endergonic synthesis of products | 51 | |
| 1120683343 | Mechanical work | Ex. Transfer of phosphate groups to special motor proteins in muscle cells causes proteins to change shape and pull on protein filaments, causing cells to contract | 52 | |
| 1120683344 | Transport work | ATP drives active transport of solutes across membrane against concentration gradient by phosphorylating transport proteins | 53 | |
| 1120683345 | Activation energy (Ea) | Amount of energy that reactants must absorb before a chemical reaction will start | 54 | |
| 1120683346 | Enzymes | Molecules that function as biological catalysts, increasing the rate of a reaction without being consumed by the reaction -almost all are proteins | 55 | |
| 1120683347 | Substrate | Specific reactant that an enzyme acts on | 56 | |
| 1120683348 | Active site | Part of enzyme where substrate molecule attaches (by weak chemical bonds) | 57 | |
| 1120683349 | Induced fit | Active site changes shape slightly to embrace substrate | 58 | |
| 1120683350 | Cofactors | Non protein molecules required for functioning of enzyme -bind to active site | 59 | |
| 1120683351 | Coenzyme | Organic cofacter | 60 | |
| 1120683352 | Inhibitor | Chemical that interferes with an enzyme's activity | 61 | |
| 1120683353 | Competitive inhibitor | Substance that reduces activity of an enzyme by binding to an enzyme's active site in place of substrate -can be overcome by increasing concentration of substrate | 62 | |
| 1120683354 | Noncompetitive inhibitor | Substance that reduces activity of enzyme without entering active site | 63 | |
| 1120683355 | Allosteric site | Place where noncompetitive inhibitor binds | 64 | |
| 1120683356 | Feedback inhibition | Method of metabolic control in which a product of a metabolic pathway acts as an inhibitor of an enzyme within that pathway -used when cell is producing more of a product than needed | 65 |
