Terminal Respiration

Question 1

Another term

Answer 1

Anaerobic Respiration

Question 2

Define anaerobic respiration

Answer 2

Anaerobic respiration is the process of creating energy without the presence of oxygen.

Question 3

Why is oxygen important in relation to the electron transport chain?

Answer 3

Without oxygen, the electron transport chain (ETC) cannot continue as there is no terminal electron acceptor.

Therefore, the usual number of ATP molecules cannot be created.

Question 4

What does the anaerobic pathway utilise?

Answer 4

Pyruvate, the final product of glycolysis.

Question 5

What is reduced if the ETC is stopped?

Answer 5

Reduced activity of the reactions before this step, such as the Krebs cycle and glycolysis.

Question 6

What happens without a functioning electron transport chain?

Answer 6

Without the functioning ETC there are an excess of NADH and pyruvate.

Question 7

What happens to pyruvate in the absence of a functioning electron transport chain?

Answer 7

Pyruvate is reduced to lactate (lactic acid) by NADH, yielding NAD+.

This reaction is catalyzed by the enzyme lactate dehydrogenase.

By recycling NAD+, the process of glycolysis is able to continue as the supply of NAD+ has been replenished.

Question 8

What does glycolysis produce?

Answer 8

2 net ATP molecules, which can be used for energy.

Question 9

What must happen to lactate produced as a result of anaerobic respiration?

Answer 9

The lactate produced as a result of anaerobic respiration must be removed from the blood as it is acidic.

Question 10

What are the two ways to remove lactate from the blood?

Answer 10

Lactate is transported to metabolically active cells, such as in the heart and brain. Here it is converted back to pyruvate, which is then utilised in the Krebs cycle.

Lactate is transported to the liver and converted to pyruvate. Pyruvate is then used in the process of gluconeogenesis to create more glucose