Q.
The figure given below shows a small part of human lung where exchange of gas takes place. In which one of the options given below, the one part A, B, C or D is correctly identified along with its function.
A) A – Alveolar cavity - main site of exchange of respiratory gases
B) D – Capillary wall - exchange of gases takes place here
C) B - Red blood cell - transport of mainly haemoglobin
D) C - Arterial capillary – passes oxygen to tissues
Explanation
Alveoli are the primary sites of exchange of gases. The exchange of gases ($O_{2}$and C$O_{2}$) between the alveoli and the blood capillary occurs by simple diffusion.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.