chapter 8

Question 1

first law of thermodynamics

Answer 1

if you have energy it can’t disappear

Question 2

second law of thermodynamics

Answer 2

every transfer of energy always increases entropy (disorder) of the universe

Question 3

metabolism

Answer 3

all the chemical reactions that take place in your body

Question 4

metabolic pathway

Answer 4

molecule is altered series of steps to produce a product

Question 5

catabolic pathways

Answer 5

release energy by breaking down complex molecules to simpler compounds

Question 6

anabolic pathway

Answer 6

consume energy to build complex molecules from simpler ones
ex. synthesis of proteins

Question 7

bioenergetics

Answer 7

study of how energy flows through organisms

Question 8

energy

Answer 8

the capacity to cause change, can be used to do work

Question 9

kinetic energy

Answer 9

energy associated with motion

Question 10

thermal energy

Answer 10

kinetic energy associated with random movements of atoms or molecules

Question 11

heat

Answer 11

energy transfer from one object to another

Question 12

potential energy

Answer 12

energy that matter possesses because of its location
ex. higher up —> more potential energy

Question 13

chemical energy

Answer 13

potential energy available for release in chemical reactions

Question 14

thermodynamics

Answer 14

the study of energy transformation in a collection of matter

Question 15

open system

Answer 15

energy and matter is transferred between the system and its surroundings

Question 16

entropy

Answer 16

the measure of molecular disorder or randomness

Question 17

how do organisms increase entropy of surroundings

Answer 17

through metabolism (breaking down food to release heat)

Question 18

spontaneous process

Answer 18

occur without energy input

Question 19

processes that decrease entropy

Answer 19

nonspontaneous processes (require energy)

Question 20

free energy

Answer 20

the portion of a systems energy that can do work when temp and pressure are uniform throughout the system, as a living cell

Question 21

ΔG

Answer 21

can be used to determine whether it is spontaneous or not

Question 22

ΔG=

Answer 22

g final state-g initial state

Question 23

negative delta g

Answer 23

system loses free energy and becomes more stable

Question 24

higher g

Answer 24

more unstable

Question 25

lower g

Answer 25

more stable

Question 26

equilibrium

Answer 26

max stability

Question 27

exergonic reaction

Answer 27

energy outward- release of energy to its surroundings

Question 28

endergonic reaction

Answer 28

absorbs free energy from surroundings

Question 29

magnitude of delta g

Answer 29

determines the max amount f work an exergonic reaction can perform

Question 30

breaking bonds ___ energy

Answer 30

requires

Question 31

what would happen if we reached equilibrium

Answer 31

we would die

Question 32

how do we never reach equilibrium

Answer 32

steady inflow of glucose and release of wast products

Question 33

chemical work

Answer 33

pushes endergonic reactions

Question 34

transport work

Answer 34

pumps substances across membranes against the direction of spontaneous movement

Question 35

mechanical work

Answer 35

such as beating cilia or contracting muscle cells

Question 36

energy coupling

Answer 36

using exergonic processes to drive endergonic reactions

Question 37

how to get energy from atp

Answer 37

breaking the phosphate bond in atp to make it adp

Question 38

are coupled reactions endergonic or exergonic

Answer 38

exergonic

Question 39

phosphorylation

Answer 39

transfer of a phosphate group from atp to another molecule -powers endergonic reactions

Question 40

phosphorylated intermediate

Answer 40

the recipient molecule from phosphorylation that is less stable with more free energy

Question 41

atp hydrolysis powers what?

Answer 41

transport and mechanical work

Question 42

how to make atp

Answer 42

add phosphate group to adp

Question 43

atp cycle

Answer 43

shuttling of inorganic phosphate and energy -couples energy-yielding processes to energy-consuming ones

Question 44

catalyst

Answer 44

chemical agents that speed up reactions

Question 45

enzymes

Answer 45

macromolecules (usually proteins) that act as catalysts in reactions

Question 46

activation energy

Answer 46

amount of energy needed to break a bond

Question 47

transition state

Answer 47

when molecules are at their unstable state and are being pushed to their products

Question 48

what determines the rate of a reaction

Answer 48

activation energy

Question 49

what does adding heat do to a reaction

Answer 49

causes proteins to denature and speeds up all reactions

Question 50

catalysis

Answer 50

the process by which a catalyst selectively speeds up a reaction without itself being consumed

Question 51

how does an enzyme work

Answer 51

lowers the activation energy of a molecule

Question 52

substrate

Answer 52

reactant that an enzyme acts on

Question 53

enzyme-substrate complex

Answer 53

when the substrate is bonded to the enzyme

Question 54

active site

Answer 54

where the substrate bonds to the enzyme

Question 55

induced fit

Answer 55

when the enzyme changes shape to tighten around the substrate

Question 56

cofactors

Answer 56

nonprotein helpers that bind to an enzyme permanently or with a substrate

Question 57

coenzymes

Answer 57

organic cofactors

Question 58

competitive inhibitors

Answer 58

closely resemble a substrate and binds to the enzymes active site

Question 59

noncompetitive inhibitors

Answer 59

bind to another part of the enzyme away from the active site -causes enzyme to change shape

Question 60

examples of irreversible enzyme inhibitors

Answer 60

toxins and poisons

Question 61

allosteric regulation

Answer 61

when a regulatory molecule binds to a protein at one site and affected the proteins function on the other side

Question 62

cooperativity

Answer 62

substrate binds to one. active site triggers a shape change in the enzyme that stabilizes the active for for all other sites

Question 63

feedback inhibition

Answer 63

have enough of a product so the metabolic pathway shuts down