2.3: Metabolic rate

Question 1

Define metabolic rate

Answer 1

the energy expended by an animal per unit of time

Question 2

Describe 3 methods and the equipment used to measure and compare metabolic rate

Answer 2

Calorimeter - temperature change
oxygen probe/respirometers - oxygen consumption
carbon dioxide probe - carbon dioxide production.

Question 3

What do organisms with a high metabolism require?

Answer 3

more efficient delivery of oxygen to cells

Question 4

compare the metabolic rate of birds and humans, amphibians and reptiles and fish.

Answer 4

fish have the lowest metabolic rate, reptiles and amphibians have a medium metabolic rate while humans and birds have the highest metabolic rate.

Question 5

Compare the anatomy and physiology of heart chambers and circulation in fish, amphibians, reptiles, mammals and birds.

Answer 5

fish have one atrium and one ventricle in their heart so fish have a single circulatory system.
reptiles and amphibians have two atria and one ventricle so their circulatory system goes through twice
birds and humans have two atrium and two ventricles and their circulatory system also goes through twice

Question 6

Describe the differences between a complete double, incomplete double and single circulatory system.

Answer 6

a complete double circulatory system has two atriums and two ventricles
an incomplete double circulatory system has two atriums and one ventricle
a single circulatory system has one atrium and one ventricle

Question 7

Explain why complete double circulatory systems enable higher metabolic rates to be maintained.

Answer 7

due to oxygenated and deoxygenated blood not mixing so the oxygenated can be pumped at high pressure and it requires more energy