12 Respiration

Question 1

Respiration

Answer 1

Chemical reactions in cells that break down nutrient molecules to release energy.
Glucose + oxygen –> Carbon dioxide + water (+ ENERGY)
C6H12O6 + 6O2 → 6CO2 + 6H2O

Question 2

What do we need energy for

Answer 2

Muscle contraction
Protein synthesis
Active transport
Cell division and growth
Passage of nerve impulses
Maintenance of constant body temp

Question 3

Aerobic respiration

Answer 3

Chemical reactions in cells in which nutrient molecules are broken down using oxygen to release energy.

Question 4

Anaerobic respiration in humans

Answer 4

Anaerobic respiration releases less energy than aerobic respiration but it does this more quickly. The product of this reaction is lactic acid. This builds up in muscles causing pain and tiredness, which can lead to cramp.
glucose → lactic acid

Question 5

Anaerobic respiration

Answer 5

A chemical reaction in cells to break down nutrient molecules to release energy without using oxygen.

Question 6

Anaerobic respiration in yeast

Answer 6

glucose → alcohol + carbon dioxide
C6H12O6 → 2C2H5OH + 2CO2

Question 7

Oxygen debt

Answer 7

The amount of oxygen needed after vigorous exercise in order to break down the lactic acid produced by anaerobic respiration.

Question 8

What actions does the body take to brake down lactic acid

Answer 8

Aerobic respiration in the liver to break down the lactic acid into carbon dioxide and water.
Maintaining a higher heart rate for a time after stopping exercise. This is so that lactic acid can be transported in the blood from the muscles to the liver.
Maintaining deeper and faster breathing for a time after stopping exercise. This provides the oxygen your liver needs to break down the lactic acid.