Chapter 6 Exam 2

Question 1

what does ATP do

Answer 1

provide energy that all cells can use to perform work of the cell

Question 2

where do phototrophs get their energy from

Answer 2

sunlight

Question 3

where do chemotrophs get their energy from

Answer 3

chemical compounds

Question 4

what are autotrophs

Answer 4

self feeder that make own organic sources of carbon

Question 5

what are heterotrophs

Answer 5

other feeders rely on other organism for their organic sources of carbon

Question 6

what is metabolism

Answer 6

building and breaking down of carbon sources to harness or release energy

Question 7

what is catabolism

Answer 7

breakdown of molecules to smaller units using ATP

Question 8

what is anabolism

Answer 8

building of molecules from smaller units using ATP

Question 9

what is potential energy

Answer 9

stored energy released when there’s a change in objects structure or position

Question 10

what is kinetic energy

Answer 10

energy of motion

Question 11

what is an endergonic reaction

Answer 11

-non spontaneous
-anabolic
-energy required
+Delta G

Question 12

what is an exergonic reaction

Answer 12

• spontaneous
• catabolic
• energy released
• Delta G

Question 13

what kind of reaction is ATP hydrolysis

Answer 13

exergonic

Question 14

what is the equation for ATP hydrolysis

Answer 14

ATP + H20 -> ADP and Pi

Question 15

what is energetic coupling

Answer 15

when a process has 2 processes where one is exergonic and one is endergonic

Question 16

describe the interactions between substrate and active site

Answer 16

they are weak noncovlane interactions or transient covalent bonds that stabilize the transition state and decreases activation energy required for rxn

Question 17

what is the Gibbs free energy equation

Answer 17

Delta G = Delta H -TDelta S

Question 18

what is enthalpy

Answer 18

(H) total energy available

Question 19

what is entropy

Answer 19

(S) degree of disorder

Question 20

What happens in reactions with a more negative DeltaG than ATP hydrolysis

Answer 20

they donate a phosphate group to ADP

Question 21

what happens in reactions with a more positive DeltaG than ATP hydrolysis

Answer 21

it receives a phosphate group from ATP

Question 22

how is the active site formed

Answer 22

amino acids are folding in such a way bringing together to form the active site

Question 23

how are enzymes specific

Answer 23

1. they recognize a unique substrate or class of substrates

2. they catalyze only one reaction or a limited number of reactions

Question 24

what are the two types of inhibitors

Answer 24

irreversible inhibitors and reversible inhibitors

Question 25

what are the two types of reversible inhibitors

Answer 25

competitive and noncompetitive

Question 26

what do irreversible inhibitors do

Answer 26

form covalent bonds with enzymes and irreversible inactivate them

Question 27

what do reversible inhibitors do

Answer 27

form weak bonds with enzymes and easily dissociate them

Question 28

what do reversible competitive inhibitors do

Answer 28

bind to active site of enzyme and prevent the substrate from binding. they compete with substrate for active site

Question 29

what do reversible noncompetitive inhibitors do

Answer 29

bind to a site different from active site. binding of noncompetitive inhibitor causes decrease in rate that enzymes convert substrate to product

Question 30

what is an allosteric enzyme

Answer 30

activated o inhibited when binding to another molecule changes its shape

Question 31

what is an example of an allosteric enzyme

Answer 31

threonine dehydratase

Question 32

what do cofactors and coenzymes do

Answer 32

cause an enzyme to change shape when binding a substrate

Question 33

what happens when a substrate binds to the enzymes active site and a shape changes (induced fit)

Answer 33

results in tighter binding of substrate to active site