METABOLIC RATE U2

Question 1

State the meaning of metabolic rate and how it can be measured

Answer 1

Metabolic rate is the amount of energy an organism will use within a given time.

Metabolic rates can be measured and compared by using:

Oxygen consumption using respirometers and oxygen probes.
Carbon dioxide production measured using respirometers and carbon dioxide probes.
Heat production – Using calorimeters.

Question 2

Compare birds, mammals, reptiles, amphibians and fish in terms of metabolic rate

Answer 2

Organism with high metabolic rates require a more efficient delivery of oxygen to cells.

Birds and mammals have higher metabolic rates than reptiles and amphibians, which in turn have higher metabolic rates than fish.

Question 3

Describe the anatomy and physiology of heart chambers and circulatory systems in fish

Answer 3

Fish have a single circulatory system consisting of one atrium and one ventricle.

Question 4

Describe the anatomy and physiology of heart chambers and circulatory systems in amphibians and reptiles

Answer 4

Amphibians and most reptiles have an incomplete double circulatory system consisting of two atria and one ventricle.

Question 5

Describe the anatomy and physiology of heart chambers and circulatory systems in birds and mammals

Answer 5

Birds and mammals have a complete double circulatory system consisting of two atria and two ventricles.

Question 6

State the advantage of complete double circulatory systems

Answer 6

Complete double circulatory systems enable higher metabolic rates to be maintained. There is no mixing of oxygenated and deoxygenated blood. Oxygenated blood can be pumped out at a higher pressure. This enables more efficient oxygen delivery to the cell.