anaerobic respiration

Question 1

Explain why an oxygen debt develops during exercise. ( 3 marks)

Answer 1

-Anaerobic respiration occurs
- lactic acid builds up in the muscles
- and oxygen is needed to react with lactic acid(to remove it from cells)

Question 2

Explain why the muscles may become fatigued during exercise. ( 2 marks)

Answer 2

-Anaerobic respiration occurs/glucose undergoes incomplete oxidation.
- and lactic acid builds up in the muscles

Question 3

Incomplete Oxidation

Answer 3

this happens in anaerobic respiration because there is not enough oxygen - it means there is not enough oxygen to break up the glucose completely so lactic acid is made.

Question 4

Ethanol

Answer 4

This is produced by yeast during anaerobic respiration (fermentation) and then is used to make alcoholic drinks.

Question 5

What is the equation of fermentation?

Answer 5

Glucose > Carbon Dioxide + Ethanol + (energy)

Question 6

Why does heart rate and breathing rate stays high after exercise? ( 6 marks)

Answer 6

-Not enough oxygen to respiring cells (e.g. muscles) during exercise
- Therefore anaerobic respiration occurs
- This produces lactic acid
- Lactic acid causes cramp and muscle fatigue
- after exercise extra oxygen is needed
- to break down the lactic acid
- this is called oxygen debt
- Breathing rate stays high to get the extra oxygen in the body
- Heart rate stays high to deliver the oxygen to the cells in the blood

Question 7

equation for anaerobic respiration in animals.

Answer 7

Glucose ——-> Lactic acid + (releases some energy)

Question 8

Oxygen Debt

Answer 8

When anaerobic respiration produces lactic acid this is the amount of oxygen needed to break down the lactic acid.

Question 9

Give one advantage and disadvantage of Anaerobic respiration. ( 2 marks)

Answer 9

Advantage - does not need oxygen/does not release carbon dioxide
Disadvantage - releases less energy than anaerobic respiration/produces lactic acid

Question 10

Compare anaerobic respiration in a yeast cell with anaerobic respiration in a muscle cell. ( 3 marks)

Answer 10

Any 2 from
- both happen in the absence of oxygen
- both use glucose
- yeast produces carbon dioxide but muscles do not
- yeast produces ethanol but muscles produce lactic acid

Question 11

Anaerobic respiration can take place in yeast cells. Give another name for this process. ( 1 mark)

Answer 11

Fermentation

Question 12

Anaerobic

Answer 12

Respiration that does not require oxygen, this gives out LESS energy that aerobic respiration

Question 13

Describe the body changes that occur during exercise

Answer 13

A chemical reaction that takes place in the mitochondria of all cells in all living things to provide them with energy