5.5 Anaerobic respiration

Question 1

What is anaerobic respiration?

Answer 1

The partial breakdown of hexoses to produce a limited yield of ATP in the absence of oxygen

Question 2

What is the difference in ATP yield of anaerobic respiration compared to aerobic?

Answer 2

Aerobic = 38
Anaerobic = 2

Question 3

Which is the only process that continues in anaerobi respiration?

Answer 3

Glycolysis

Question 4

How is lactate produced?

Answer 4

As a by-product of the conversion of pyruvate

Question 5

How is lactate converted back into pyruvate?

Answer 5

Transported to the liver through the bloodstream
Helped by lactate dehydrogenase
Involves conversion of NAD to reduced NAD

Question 6

How does lactate affect mammals?

Answer 6

Acidic, and so increases pH
Results in muscle fatigue
Drop in pH can cause enzymes to denature
Not enough ATP results in death

Question 7

How does anaerobic respiration affect microorganisms?

Answer 7

Only glycolysis continues
Pyruvate is decarboxylated to form ethanal
Ethanal reduced to ethanol using reduced NAD (to produce oxidised NAD to further glycolysis)
Ethanol dissolves cell membranes when concentration is above 12%