Which of the following body activities require energy?

• A. Muscle contraction
• B. Facilitated diffusion
• C. Osmosis
• D. Passive diffusion

Answer: (A)

Verified step by step guidance

1. Understand the concept of energy requirement in physiological processes. Energy is typically required for active processes that involve movement or transport against a gradient.
2. Identify muscle contraction as an active process. Muscle contraction requires energy in the form of ATP to facilitate the interaction between actin and myosin filaments, leading to movement.
3. Examine facilitated diffusion. Facilitated diffusion is a passive transport process where molecules move across cell membranes through protein channels, without the need for energy.
4. Consider osmosis. Osmosis is the passive movement of water molecules across a semipermeable membrane from a region of lower solute concentration to higher solute concentration, requiring no energy.
5. Review passive diffusion. Passive diffusion involves the movement of molecules from an area of higher concentration to an area of lower concentration, driven by the concentration gradient, and does not require energy.