Question

what process concentrates calcium within the cell? facilitated diffusion osmosis active transport

Explanation:

To determine the process that concentrates calcium within the cell, we analyze each option:

• Facilitated diffusion: Moves substances down their concentration gradient (from high to low) through transport proteins. It does not concentrate a substance (which requires moving against the gradient).
• Osmosis: Is the diffusion of water across a semipermeable membrane, not related to ion concentration like calcium.
• Active transport: Requires energy (e.g., ATP) to move substances against their concentration gradient (from low to high), which is necessary to concentrate calcium inside the cell (as calcium is often at a lower concentration inside the cell initially, and concentrating it requires moving against the gradient).

Answer:

C. active transport