Question

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.

Options

• A - Alveolar cavity - main site of exchange of respiratory gases

• D - Capillary wall - exchange of gases takes place here

• B - Red blood cell - transport of mainly haemoglobin

• C - Arterial capillary - passes oxygen to tissues

Answer 1

A - Alveolar cavity - main site of exchange of respiratory gases