Veterinary Technician Practice Exam

What process describes the use of cell membranes to control the movement of substances?

1. Diffusion

2. Absorption

3. Osmosis

4. Filtration

The correct answer is: Diffusion

The process that most accurately describes the use of cell membranes to control the movement of substances is diffusion. Diffusion involves the movement of molecules from an area of higher concentration to an area of lower concentration and occurs across cell membranes. It is a fundamental process in biology, allowing cells to obtain necessary substances and eliminate waste products effectively. While absorption typically refers to the uptake of substances by cells or tissues, it does not specifically address the essential function of cell membranes in regulating movement. Osmosis is a specific form of diffusion concerning the movement of water across a semipermeable membrane, and filtration refers to the separation of particles based on size or pressure differences, rather than the controlled movement of substances through cell membranes.