Question

Which are the major modes of active transport?

• A. Exocytosis, endocytosis, and pumps
• B. Simple diffusion, endocytosis, and exocytosis
• C. Simple diffusion, facilitated diffusion, and osmosis
• D. Exocytosis, endocytosis, and osmosis

Hint:

Active transport requires energy to move molecules against their concentration gradient. Exocytosis, endocytosis, and pumps are all examples of active transport.

Answer 1

The Correct Option is A

Let's analyze each option:
(1) Exocytosis, endocytosis, and pumps: Active transport requires energy to move substances against their concentration gradient. Exocytosis and endocytosis are processes that require energy for vesicle formation and movement. Pumps, such as the sodium-potassium pump, also require energy to move ions against their gradient. This is the correct answer.
(2) Simple diffusion, endocytosis, and exocytosis: Simple diffusion is a passive transport process that does not require energy. This option is not correct because active transport requires energy.
(3) Simple diffusion, facilitated diffusion, and osmosis: All of these processes are passive transport mechanisms and do not require energy. Hence, this is not the correct answer.
(4) Exocytosis, endocytosis, and osmosis: Osmosis is a passive process, so this option is not correct.
Conclusion: The correct answer is Option 1: Exocytosis, endocytosis, and pumps as these are the major modes of active transport.