Question

state three common features of all the respiratory organs like skin, gills and lungs.

2]explain why when air is taken in and let out during breathing, the lungs always contain residual volume of air?

Answer 1

The features that are common to all respiratory organs are

• They have a large surface area for exchange of gases
• The membranes of all respiratory organs are thin for better diffusion.
• All of them have rich blood supply for better transportation of gases.