Chaapter 8

Question 1

metabolism

Answer 1

the totality of an organisms chemical reactions

Question 2

what property does metabolism have

Answer 2

the emergent property of life that arises from interactions between molecules within a cell

Question 3

catabolic pathways

Answer 3

release energy by breaking down complex molecules into simpler ones

Question 4

anabolic pathway

Answer 4

consume energy to build complex molecules from simpler ones

Question 5

bioenergetics

Answer 5

the study of how organisms manage their energy resources

Question 6

kinetic energy

Answer 6

energy associated with motion

Question 7

heat energy (thermal)

Answer 7

kinetic energy associated with random movement of atoms or molecules

Question 8

potential energy

Answer 8

energy that matter possesses because of its location of structure

Question 9

chemical energy

Answer 9

potential energy available for release in a chemical reaction

Question 10

1st law of thermodynamics

Answer 10

energy can be transferred and transformed but cannot be created or destroyed

Question 11

2nd law of thermodynamics

Answer 11

every energy transfer or transformation increases entropy or the universe

Question 12

free energy

Answer 12

energy that can do work when temperature and pressure are uniform (living)

Question 13

what does free energy measure

Answer 13

is a measure of a systems instability, it’s tendency to change to a more stable state

Question 14

exergonic reaction

Answer 14

proceeds with a net release of free energy and is spontaneous

Question 15

endergonic reaction

Answer 15

absorbs free energy from its surroundings and is nonspontaneous

Question 16

energy coupling

Answer 16

the use of exergonic process to drive an endergonic one

Question 17

phosphorylation

Answer 17

transferring a phosphate group to some other molecule

Question 18

substrate

Answer 18

reactant that an enzyme acts on

Question 19

active site

Answer 19

the region on the enzyme where the substrate binds

Question 20

induced fit

Answer 20

brings chemical groups of the active site into positions that enhance their ability to catalyze the reaction

Question 21

how can the active site lower activation energy

Answer 21

orienting substrates correctly, straining substrate bonds, providing a favorable microenvironment, or covalently bonding to the substrate

Question 22

cofactors

Answer 22

nonprotein enzyme helpers

Question 23

coenzymes

Answer 23

organic cofactors

Question 24

competitive inhibitors

Answer 24

bind to the active site of an enzyme competing with the substrate

Question 25

noncompetitive inhibitors

Answer 25

bind to another part of the enzyme, causing the enzyme to change shape and making the active site less effective

Question 26

allosteric regulation

Answer 26

describes cases where the proteins function at one site is affected by binding of a regulatory molecular at another site

Question 27

activator

Answer 27

stabilizes the active form of the enzyme

Question 28

inhibitor

Answer 28

stabilizes the inactive form of the enzyme

Question 29

feedback inhibition

Answer 29

the end product of a metabolic pathway shuts down the pathway