Question

Gaseous exchange in cells takes place by___________

• A. Osmosis
• B. Exocytosis
• C. Diffusion
• D. Endocytosis

Answer 1

Answer: (C)

Diffusion

Diffusion is a process where the molecules move from region of higher concentration to the lower concentration. It is a passive process, which always takes place towards the diffusion gradient. It plays an integral role in the exchange of gases at the cellular level. For example, the oxygenated blood in the arteries releases the oxygen to the extracellular fluid and further to the cells with an exchange of carbon dioxide. This takes place due to the diffusion gradient created by the high concentration of oxygen in the blood as compared to the cell.