ap bio chap 8 Flashcards

39803551	metabolism	The totality of an organism's chemical reactions is called	0
39803552	metabolism	is an emergent property of life that arises from interactions between molecules within the orderly environment of the cell.	1
39803553	catabolic pathways	release energy by breaking down complex molecules to simpler compounds.	2
39803554	cellular respiration	A major pathway of catabolism is _________, in which the sugar glucose is broken down in the presence of oxygen to carbon dioxide and water.	3
39803555	anabolic pathways	consume energy to build complicated molecules from simpler compounds. They are also called biosynthetic pathways.	4
39803556	bioenergetics	is the study of how organisms manage their energy resources	5
39803557	heat or thermal energy	is kinetic energy associated with the random movement of atoms or molecules.	6
39803558	chemical energy	is a form of potential energy stored in molecules because of the arrangement of their atoms.	7
39805152	thermodynamics	Another way to state the second law of thermodynamics is for a process to occur spontaneously, it must increase the entropy of the universe.	8
39805153	system	refers to the matter under study and the surroundings include everything outside the system	9
39806284	closed system	approximated by liquid in a thermos, is isolated from its surroundings.	10
39806285	open system	energy and matter can be transferred between the system and its surroundings.	11
39806286	first law of thermodynamics	states that energy can be transferred and transformed, but it cannot be created or destroyed.	12
39806287	entropy	is a quantity used as a measure of disorder or randomness	13
39806288	second law of thermodynamics	states that every energy transfer or transformation increases the entropy of the universe.	14
39806289	spontaneous	describes a process that can occur without an input of energy.	15
39806290	free energy change	The ______________of a reaction tells us whether it is spontaneous.	16
39806291	free energy	is the portion of a system's energy that is able to perform work when temperature and pressure is uniform throughout the system, as in a living cell.	17
39806292	G	= H − TS, where T is temperature in Kelvin units.	18
39806293	free energy	can be thought of as a measure of the stability of a system.	19
40077513	negative	change in G must be _________ for a process to be spontaneous	20
40077514	exergonic	An _________ reaction proceeds with a net release of free energy; G is negative.	21
40077515	endergonic	An __________ reaction is one that absorbs free energy from its surroundings.change in g is positive	22
40077516	energy coupling	the use of an exergonic process to drive an endergonic one.	23
40077517	ATP	a type of nucleotide consisting of the nitrogenous base adenine, the sugar ribose, and a chain of three phosphate groups.	24
40077518	phosphorylated	• In the cell, the energy from the hydrolysis of ATP is directly coupled to endergonic processes by the transfer of the phosphate group to another molecule. This recipient molecule is now	25
40077519	hydrolysis of ATP	• Mechanical, transport, and chemical work in the cell are nearly always powered by the	26
40077520	phosphate group	• ATP is a renewable resource that can be regenerated by the addition of a _____________ to ADP.	27
40077521	Catabolic	________(exergonic) pathways, especially cellular respiration, provide the energy for the exergonic regeneration of ATP.	28
40077522	activation energy	The initial investment of energy for starting a reaction is the	29
40077523	transition state	At the summit, the molecules are in an unstable condition, the __________	30
40077524	enzyme-substrate complex	• The enzyme binds to a substrate, or substrates, forming an ________________	31
40077525	weak interactions	• In most cases, substrates are held in the active site by ______________, such as hydrogen bonds and ionic bonds.	32
40077526	R groups	________of a few amino acids on the active site catalyze the conversion of substrate to product.	33
40077527	microenvironment	R groups at the active site may create a ______________ that is conducive to a specific reaction.	34
40077528	low	At ____ substrate concentrations, an increase in substrate concentration speeds binding to available active sites.	35
40077529	increases	As temperature _________, collisions between substrates and active sites occur more frequently as molecules move more rapidly.	36
40077530	6 and 8	Optimal pH falls between pH __________ for most enzymes.	37
40077531	cofactors	• Many enzymes require nonprotein helpers, called ___________, for catalytic activity.	38
40077532	coenzymes	Organic cofactors are called _________	39
40077533	inhibitors	Binding by __________ prevents enzymes from catalyzing reactions	40
40077534	competitive inhibitors	• Some reversible inhibitors, called ____________, resemble the substrate and compete for binding to the active site.	41
40077535	Noncompetitive inhibitors	_____________ impede enzymatic reactions by binding to another part of the molecule.	42
40077536	allosteric	Metabolic control often depends on ________ regulation.	43
40077537	allosteric site	a specific receptor on the enzyme away from the active site.	44
40077538	activator, inhibitor	• The binding of an __________ stabilizes the conformation that has functional active sites, while the binding of an __________ stabilizes the inactive form of the enzyme.	45
40077539	cooperativity	• In enzymes with multiple catalytic subunits, binding by a substrate to one active site stabilizes favorable conformational changes at all other subunits, a process called .	46
40077540	feedback inhibition	• A common method of metabolic control is ____________ in which an early step in a metabolic pathway is switched off by the pathway's final product.	47