Microbial metabolism

Question 1

What is the terminal electron acceptor in aerobic respiration?

Answer 1

Oxygen

Aerobic respiration occurs in the presence of oxygen.

Question 2

What is the terminal electron acceptor in anaerobic respiration?

Answer 2

Anything but oxygen

Anaerobic respiration can involve various substances as electron acceptors.

Question 3

Which processes involve substrate-level phosphorylation?

Answer 3

Glycolysis and Krebs Cycle

Substrate-level phosphorylation refers to ATP production via direct transfer of a phosphate group.

Question 4

Which process involves oxidative phosphorylation?

Answer 4

Electron transport chain

Oxidative phosphorylation is the production of ATP using energy derived from the electron transport chain.

Question 5

List the bioenergetics pathways to be familiar with.

Answer 5

• Glycolysis
• Fermentation
• Intermediate step
• Krebs Cycle
• Electron transport chain

These pathways are key to understanding cellular respiration.

Question 6

What is the ATP equivalent for NADH?

Answer 6

3

NADH is a high-energy electron carrier that contributes to ATP production.

Question 7

What is the ATP equivalent for FADH2?

Answer 7

2

FADH2 is another electron carrier but yields less ATP than NADH.

Question 8

What goes into glycolysis?

Answer 8

Glucose And 2NAD+

Glycolysis begins with the breakdown of glucose to produce pyruvate.

Question 9

What are the products of glycolysis?

Answer 9

2 Pyruvate, 2 ATP, 2 NADH

Glycolysis results in the production of pyruvate along with ATP and NADH.

Question 10

What goes into the Krebs Cycle?

Answer 10

Acetyl-CoA, GDP,
3 NAD+, and FAD

The Krebs Cycle begins with the entry of acetyl-CoA derived from pyruvate.

Question 11

What are the products of the Krebs Cycle?

Answer 11

3 NADH, 1 FADH2, 1 ATP (GTP), 2 CO2

12 ATP equivalents

The Krebs Cycle generates high-energy electron carriers and ATP while releasing CO2.

Question 12

What occurs during the intermediate step?

Answer 12

Conversion of pyruvate to acetyl-CoA

Produces 6 ATP equivalents (2NADH)

This step connects glycolysis to the Krebs Cycle.

Question 13

What are the products of the intermediate step?

Answer 13

Acetyl-CoA, NADH, CO2

The intermediate step produces acetyl-CoA and releases CO2.

Question 14

What goes into fermentation?

Answer 14

Glucose

Fermentation starts with glucose and typically occurs in anaerobic conditions.

Question 15

What are the products of fermentation?

Answer 15

2 NAD+, CO2, and Lactic acid or ethanol

Depending on the type of fermentation, the end products vary.