Fish gills are covered by a bony flap called:

Which part of the organism across around which the gas exchange takes place ?

The respiratory system of insects is called:

Guard cells become turgid by actively transporting which of the following ions ?

The water proof layer that protects human skin.

The respiratory organ of fish is called:

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

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

The branchioles end in millions of tiny interconnected cavities called:

Which one of the following is the by-product gas of photosynthesis?