Bioenergetics

Question 1

What is bioenergetics?

Answer 1

Branch of biochem that focuses on how cells tranform energy

Question 2

What is the first law of thermodynamics?

Answer 2

Energy cannot be created or destroyed only converted

Question 3

What is the second law of thermodynamics?

Answer 3

Entropy must increase of a reaction is to be spontaneous

Question 4

What are energy releasing reactions called?

Answer 4

Exergonic

Question 5

What are energy dependant reactions called?

Answer 5

Endergonic

Question 6

What kind of reaction when ^G is negative?

Answer 6

Exergonic

Question 7

What kind of reaction when ^G is positive?

Answer 7

Endergonic

Question 8

Is the reaction spontaneous or not spontaneous in standard conditions when the reaction is endergonic (^G+)

Answer 8

Not spontaneous

Question 9

Is the reaction spontaneous or not spontaneous in standard conditions when the reaction is exergonic (^G-)

Answer 9

Spontaneous

Question 10

What is used to drive the synthesis of ATP?

Answer 10

Energy stored in NADH

Question 11

What is NADH?

Answer 11

Reduced nicotinamide adenine dinucleotide

Question 12

What is FADH2?

Answer 12

Reduced flavin adenine dinucleotide

Question 13

What are NADH and FADH2?

Answer 13

Reduced coenzymes

Question 14

How can the cell regulate enzyme activity?

Answer 14

Change number of enzymes
Change catalytic activity of preexisting enzymes

Question 15

How can the number of enzymes be regulated?

Answer 15

Through gene expression

Question 16

Is the regulation og number of enzymes fast or slow

Answer 16

Slow

Question 17

Can ATP be an allosteric regulator?

Answer 17

Yes for some enzymes (dependant on their allosteric and active site)

Question 18

What can regulate catalytic activity?

Answer 18

Phosphorylation
Allosteric regulation
Control of substrate concentration

Question 19

Why does the gamma bond in ATP give off the most energy?

Answer 19

Because the negative phosphates give high instability and thus high energy and there are more phosphates present when it is ATP instead of ADP

Question 20

Why is ATP so useful?

Answer 20

Because its an easy donor and easy acceptor so it transfers energy easily
Small molecule

Question 21

Are NAD and NADP usually freely diffusible or enzyme bound?

Answer 21

Freely diffusible

Question 22

Are FMN and FAD usually freely diffusible or enzyme bound?

Answer 22

Enzyme bound

Question 23

What do you produce in the catabolic pathways?

Answer 23

ATP

Question 24

Why does ATP have a high phosphoryl-transfer potential? (4)

Answer 24

Resonance stabilisation
Electrostatic repulsion
Increase in entropy
Stabilisation by hydration

Question 25

What is creatine kinase storage of?

Answer 25

Energy in the form of phosphate (energy from access ATP)

Question 26

Oxidation reactions involve the loss of what?

Answer 26

Electrons

Question 27

What can you get more energy out of: more reduced or more oxidated?

Answer 27

More reduced

Question 28

Why can you get more energy from fatty acids than glucose?

Answer 28

Because they ar more reduced

Question 29

Are fatty acids free to travel in the blood?

Answer 29

No they have to be bonded to albumin

Question 30

Which includes reduction, anabolism or catabolism?

Answer 30

Anabolism

Question 31

Which includes oxidation, anabolism or catabolism?

Answer 31

Catabolism

Question 32

Are ^G additive?

Answer 32

Yes

Question 33

Which reactions indirectly provide much of the energy needed to make ATP?

Answer 33

Oxidation-reduction

Question 34

Is NADP positive or negative?

Answer 34

Positive

Question 35

Equation for free energy change ^G=?

Answer 35

^G=^H-T^S

Question 36

Is the free energy change for a reaction dependant of the pathway by which the section occurs?

Answer 36

No, independant

Question 37

Which reactions are thermodynamically unfavourable?

Answer 37

Endergonic

Question 38

How can an endergonic reaction be driven in the forward direction?

Answer 38

By coupling it to a highly exergonic reaction

Question 39

2 forces all chemical reactions are influenced by

Answer 39

Tendency to achieve the most stable bonding state Tendency to achieve the highest degree of randomness

Question 40

Why does ATP give off so much energy?

Answer 40

High energy bonds Negative phosphate group gives high instability which gives more energy

Question 41

Why is ATP a good "middle man"?

Answer 41

Because it transfers energy easily Easy donor and easy acceptor Small molecule Simple and easy reaction

Question 42

4 compounds aside from ATP with high-energy bonds

Answer 42

1,3-bisphosphoglycerate Cr4eatine phosphate Phosphoenolpyruvate Acetyl CoA

Question 43

4 universal electron carriers

Answer 43

NAD NADP FMN FAD

Question 44

What are NAD, NADP, FMN and FAD?

Answer 44

Water-soluable coenzymes that undergo reversible oxidation and reduction

Question 45

What are activated carriers?

Answer 45

Molecules that can be split to release free energy

Question 46

What can a dietary deficiency of niacin cause?

Answer 46

Pellagra