B2.6.2 Anaerobic respiration

Question 1

When does anaerobic respiration occur and why?

Answer 1

• When insufficient oxygen is reaching the muscles.

- Muscles use anaerobic respiration to obtain energy.

Question 2

Define “anaerobic respiration”

Answer 2

• The incomplete breakdown of glucose, which produces lactic acid.

Question 3

What is the word equation for anaerobic respiration?

Answer 3

Glucose –> Energy + lactic acid

Question 4

Why is much less energy released in anaerobic respiration compared to aerobic respiration?

Answer 4

The breakdown of energy is incomplete.

Question 5

What does anaerobic respiration result in?

Answer 5

An oxygen debt.

Question 6

Why do you need to breathe hard for awhile after anaerobic respiration?

Answer 6

• To repay the “oxygen debt”.

- Getting oxygen into your muscles to oxidise lactic acid to carbon dioxide and water.

Question 7

What happens to muscles when they are subjected to long periods of vigorous activities?

Answer 7

• They become fatigued and stop contracting efficiently.

Question 8

What is one cause of muscle fatigue?

Answer 8

The build-up of lactic acid in muscles.

Question 9

How does increased heart rate removes lactic acid?

Answer 9

• Increased heart rate increases blood flowing (and the supply of oxygen) through the muscles, removing lactic acid.