Bioenergetics Flashcards

1
Q

What is the difference between NADPH and NADH?

A

The ratio of NAD+ to NADH inside the cell is high, while the ratio of NADP+ to NADPH is kept low. The role of NADPH is mostly anabolic reactions, where NADPH is needed as a reducing agent, the role of NADH is mostly in catabolic reactions, where NAD+ is needed as a oxidizing agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

why is gibbs free energy important?

A

it tells you if a reaction is going to be favorable or not

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How do cells maintain their free energy?

A

by nutrients and sunlight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If we have a reaction that needs input of energy into the system for it to proceed, what type of reaction do we have?

A

a reaction that favors its substrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what type of conditions doe delta G exist under?

A

cellular conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

can delta G naut be positive in a spontaneous reaction?

A

yes, delta G naut does sign does not tell you if the reaction will be spontaneous or nonspontaneous delta G does

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

In biochemical pathways, a reaction was processed and the delta G was calculated and was a small number, what type of reaction occurred in the reaction?

A

readily reversible reaction also know as near equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

A chemist noticed that the delta G was near equilibrium, which type of reaction is this?

A

reversible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

a chemist noticed that the delta G was far from equilibrium with a negative sign, what type of reaction is this?

A

irreversible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

which equilibrium is usually the regulatory step?

A

far from equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

which equilibrium controls the flux of the reaction?

A

far from equilibrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

if delta G is large an positive what needs to happen for this reaction to proceed?

A

it is nonspontaneous, and it must be pushed by coupling with hydrolysis of ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does ATP normally exist as?

A

magnesium 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what cells require continous free energy?

A

osmotic, electrical, mechanical, and biosynthetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why does ATP have electrostatic repulsion?

A

there are 4 negative charges in close proximity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

after a meal, glycolysis is initiated, and to allow the glucose to enter the cell glucokinase is required. in using ATP to add a phosphate group, how was ATP harnessed ?

A

by a phosphoryl group transfer

17
Q

what is the purpose of ATP in biosynthetic reactions?

A

it typically pushes the reaction

18
Q

what type of bond does acetyl CoA have?

A

thioester bond, which allows storage of energy

19
Q

what is acetyl CoA synthetase ?

A

a transient high-energy AMP-bound intermediate is formed (on an enzyme)

20
Q

when acetylCoA is formed what type of acetyl CoA is formed what type of transfer is this classified as?

A

nucleotidyl group transfer

21
Q

what is phosphagens?

A

a high E phosphoamide compound

22
Q

after eating a big meal, and sitting down to watch TV, what does happens to the elevated amount of glucose /ATP in the body??

A

it is stored as creatin kinase

23
Q

after eating a big meal and you decide to exercise, what will happen and your ATP levels are decreased and you needed more ATP how will it be made?

A

By creatin kinase

24
Q

What are the 3 energy rich thioester bonds?

A

Acetyl-CoA, Succinyl-CoA, Acyl CoA

25
when CoA-SH is complexed with something what is the complex called?
Acetyl-CoA
26
why must the net sum of delta G of a reaction need to be negative?
because cells like favorable reactions
27
when you couple glucose(14) and ATP (-30.5) and the delta G naut is equated to -16.5, what does this number mean?
since it is negative- it means that energy is being released
28
when coupling glucose with ATP, the glucose reaction is switched and the reaction reads glucose+pi---> glucose-6-p +H2O and delta G naut is 14kJ/mol, what will happen to the delta G naut?
it will become negative because now energy is being released instead of absorbed
29
can 2 reactions coupled through a common intermediate?
yes
30
what enzyme helps cellular energy homeostasis?
adenylate knase
31
the phosphotransferase kinase, adenylate kinase helps maintain cellular energy homeostasis by?
by recycling AMP back into the ATP/ADP cycle
32
GDP + ATP ---> GTP +ADP , for nucleoside triphosphates,What enzyme is used in this process tohelp cells get rephosphorylate by ATP?
nucleoside diphosphosphokinase
33
what is nucleoside diphosphosphokinase?
exchanges of phosphate groups between different nucleoside diphosphates