Gas Exchange in Animals

Question 1

What is the difference in gas exchange between simple animals and larger animals?
Why larger animals have to develop a special organ in their body for gas exchange?

Answer 1

In simple animals, such as Amoeba and the earthworm, gas exchange takes place through the body surface by diffusion. For larger animals, the body surface is not enough to obtain sufficient oxygen and remove carbon dioxide produced. Thus, special organs with a larger surface area are developed in their bodies for effective gas exchange, e.g. the gills of fish and the lungs of mammals, birds, reptiles and amphibians

Question 2

What is ventilation?

Answer 2

Exchange of air between the atmosphere and the lungs, achieved by the physical act of breathing

Question 3

What is gas exchange?

Answer 3

Exchange of oxygen and carbon dioxide between the alveoli and bloodstream via passive diffusion

Question 4

What is cellular respiration?

Answer 4

A controlled chemical reaction to release energy from organic molecules to generate energy (ATP) in cells