Question

the process by which gaseous exchange takes place through cell membrane

Answer 1

the process by which gaseous exchange takes place through cell membrane are called osmosis.and in other words it can also be says the process of respiration.

Answer 2

This process is known as simple diffusion which is a special type of osmosis. It doesn't require any energy rather it takes place due to the concentration gradient on the either sides of cell membrane.
If we talk of human body, this can be seen in alveoli in lungs. It occurs due to respiration in which there is intake of oxygen and carbon dioxide is given out.

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