An Introduction to Metabolism: Chp 8

Question 1

metabolism

Answer 1

the totality of an organism’s chemical reactions. metabolism as a whole manages the material and energy resources of the cell

Question 2

catabolic pathway

Answer 2

leads to the release of energy by the breakdown of complex molecules to simpler compounds

Question 3

anabolic pathways

Answer 3

consume energy to build complicated molecules from simpler ones

Question 4

energy

Answer 4

the capacity to do work

Question 5

kinetic energy

Answer 5

when anything is moving it has this energy

Question 6

potential energy

Answer 6

wen anything has stored energy as a result of its position or structure

Question 7

chemical energy

Answer 7

a form of potential energy, is stored in molecules, and the amount of chemical energy a molecules possesses depends on its chemical bonds

Question 8

thermodynamics

Answer 8

the study of energy transformations that occur in matter

Question 9

first law of thermodynamics

Answer 9

states that the energy of the universe is constant and that energy can be transferred and transformed, but it cannot be created or destroyed

Question 10

second law of thermodynamics

Answer 10

states that every energy transfer or transformation increases the entropy in the universe

Question 11

entropy

Answer 11

amound of disorder or randomness

Question 12

free energy

Answer 12

defined as the part of a system’s energy that is able to perform work when the temperature of a system is uniform (symbol=/\G)

Question 13

exergonic reaction

Answer 13

is one in which energy is released. Exergonic reactions occur spontaneoulsy and release free energy to the system

Question 14

endergonic reaction

Answer 14

one that requires energy in order to proceed. endergonic reactions absorb free energy; that is, they require free energy from the system

Question 15

energy coupling

Answer 15

the use of an exergonic process to drive an endergonic one. this is a key feature in the way cells manage their energy resources to do cell work

Question 16

ATP

Answer 16

primary source of energy for cells. Made up of the nitrogenous base adenine, bounded to ribose and a chain of three phosphate groupes. When a phosphate group is hydrolyzed, energy is released in an exergonic reaction

Question 17

ADP

Answer 17

when ATP trandfers one phosphate through hydrolysis ADP is the outcome.

Question 18

catalysts

Answer 18

substances that can change the rate of a reaction without being altered in the process

Question 19

enzymes

Answer 19

macromolecules that are biological catalysts

Question 20

activation energy

Answer 20

the amount of energy it takes to start a reaction, the amount of energy it takes to break the bonds of the reactant molecules. Enzymes speed up reactions by lowering the activations energy of the reaction but without changeing the free energy

Question 21

substrate

Answer 21

the reactant that the enzyme acts on

Question 22

active site

Answer 22

the part of the enzyme that binds to the substrate

Question 23

enzyme-substrate complex

Answer 23

the complex the enzyme and substrate form

Question 24

products

Answer 24

what the substrate is converted into during the catalytic cycle of an enzyme

Question 25

cofactors

Answer 25

nonprotein helpers many enzymes require to function properly

Question 26

coenzymes

Answer 26

organic cofactors

Question 27

competitive inhibitors

Answer 27

reversible inhibitors that compete with the substrate for the active site on the enzyme

Question 28

noncompetitive inhibitors

Answer 28

do not directly compete with the substrate molecule; instead, they impede enzyme activity by binding to another part of the enzyme

Question 29

allosteric

Answer 29

a specific binding site many enzyme regulators bind to on the enzyme. (once bound, the shape of the enzyme is changed either inhibiting or stimulating activity)

Question 30

feedback inhibition

Answer 30

when the end product switchs off its pathway by binding to the allosteric site of an enzyme. this increases the efficiency of the pathway by turning it off when the end product accumulates in the cell