Lecture 13

Question 1

Describe the role of NADH in glucose catabolism

Answer 1

NADH shuttle elections from glucose to electron transport chain for use in oxidative phosphorylation

Question 2

Describe redox reactions of cellular resperation

Answer 2

Glucose oxidized to CO2 and O2 is reduced to H2O

• electrons are passed from glucose to NAD+
• electron passed from NADH to oxygen at electron transport chain
• carbon of glucose is lost as CO2

Question 3

Describe (de)phosphorylation

Answer 3

ATP (in equilibrium with) ADP +Pi +energy

• transfer of phosphate from one molecule to another
• ATP production by this method is called substrate level phosphorylation

Question 4

What are the processes of aerobic cellular respiration?

Answer 4

• glycolysis
• pyruvate oxidation
• citric acid cycle
• oxidative phosphorylation

Question 5

Where are the different locations of the processes of aerobic cellular respiration

Answer 5

Glycolysis is in the cytosol

Everything else are in the mitochondrion in eukaryotes

Question 6

Describe pyruvate oxidation in eukaryotes

Answer 6

• pyruvate enters mitochondria via active transport
• Carboxyl group removed as CO2
• NAD+ reduced to NADH, two carbon fragment oxidized
• coenzyme A added to acetyl group, forms acetylCoA, has very high potential energy

Question 7

Electrons have more free energy in water or NADH

Answer 7

NADH, waters electronegativity stabilizes electrons

Question 8

What is glycolysis

Answer 8

“Sugar splitting”

• oxidizes glucose to 2 molecules of pyruvate
• H+ and electron from glucose reduce NAD+ to NADH
• ATP produced