Cellular Respiration

Question 1

How are metabolic pathways regulated?

Answer 1

• “End product Inhibition”- they are regulated by their product- stops overproduction

Question 2

A sigmoid curve is a representation of what type of inhibition?

Answer 2

A sigmoid curve is representation of cooperative allostery

Question 3

What happens to C-O bonds and C-H bonds when burning glucose?

Answer 3

When burning glucose, C-O bonds increase, C-H bonds decrease

Question 4

In what form is oxidation energy stored?

Answer 4

NAD- reduced to NADH

Question 5

How does NAD create energy? What happens when it is coupled with oxygen?

Answer 5

NADH is oxidized it releases energy
When NADH is coupled with oxygen, electrons flow away from NADH
When coupled with oxidation of glucose, e- flow toward NAD+

Question 6

What is the best electron acceptor?

Answer 6

Oxygen!

Question 7

Formula for NAD+ reduction

Answer 7

NAD+ + H+ + 2e- NADH

Question 8

What is redox potential?

Answer 8

The tendency to lose or gain electrons

Question 9

List the 4 steps of cellular respiration

Answer 9

1) Glycolysis
2) Pyruvate Processing
3) Citric Acid Cycle
4) Electron Transport and Chemiosmosis

Question 10

What are start and end products of glycolysis?

Answer 10

• ATP is used to split C6 into 2C3 (pyruvate) in cytosol

Question 11

What happens during pyruvate processing?

Answer 11

Pyruvate is oxidized to create acetyl coA. Biproducts are NADH, H+, ATP
This happens in the mitochondria

Question 12

What are products of citric acid cycle- what catalyzes this reaction?

Answer 12

• Acetyl coA gives 2CO2, FADH, NADH

- catalyzed by dehydrogenases

Question 13

What is step in cell resp that isn’t a redox reaction?

Answer 13

Only step that isn’t redox is GTP

Question 14

Electron Transport Chain

Answer 14

A series of redox reactions coupled to transport of protons across inner mitochondria membrane
- Required to get rid of NADH because cells need more ATP than NADH they need NAD+ for citric acid to continue
-

Question 15

What carries electrons through ETC?

Answer 15

Ubiquinone

Question 16

Which complex of the ETC in cellular respiration releases the most H+?

Answer 16

Complex 3

Question 17

After the ETC, what is the next step?

Answer 17

The next step is using the transported electron and the gradient set up by ETC to use ATP synthase

Question 18

High _____ shuts down glycolysis, citric acid cycle, and ETC (different for each one)

Answer 18

High ATP shuts down glycolysis
High NADH shuts down citric acid cycle
High Proton gradient shuts down ETC

Question 19

In anaerobic respiration, what happens?

Answer 19

Just glycolysis

Pyruvate is used as the main electron acceptor, to replenish NAD+.

Question 20

What is chemiosmosis?

Answer 20

Protons travel down electrochemical gradient through ATP synthase to create ATP

Question 21

Two types of fermentation

Answer 21

• Alcoholic- glycolysis gives H+ to acetaldehyde, creating ethanol
• Lactic Acid- glycolysis gives H+ to pyruvate yielding lactate as a biproduct

Question 22

Is ATP synthase endergonic or exergonic?

Answer 22

Exergonic!