The respiratory organ of fish is called:

Give an example of small organism in which the ratio of surface area to volume is high.

Write the name of the process by which the exchange of gases between an organism and its environment taking place.

Gases are diffused in and out of leaves through small openings called stomata. A stomata is surrounded by two cells called:

The branchioles end in millions of tiny interconnected cavities called:

Percentage of oxygen present in the atmosphere.

The respiratory system of insects is called:

Insects have a protective layer that covers their skin called:

Carbon dioxide and oxygen diffuse in and out of leaves through small openings called:

Name the openings in the tracheal system of insects.