Campbell Biology C&C, 7th Edition, Chapter 5 Flashcards

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