In passive transport, how does increasing temperature generally affect the rate of diffusion across a medium?

• A. It increases the diffusion rate because molecules have greater kinetic energy and move faster.
• B. It stops diffusion entirely once a threshold temperature is reached.
• C. It has no effect on diffusion rate because diffusion depends only on concentration gradient.
• D. It decreases the diffusion rate because molecules collide less frequently at higher temperatures.

Answer: (A)

Verified step by step guidance

1. Understand that passive transport, specifically diffusion, is the movement of molecules from an area of higher concentration to an area of lower concentration without the use of cellular energy.
2. Recall that temperature affects the kinetic energy of molecules: as temperature increases, molecules move faster because they have more kinetic energy.
3. Recognize that faster molecular movement increases the frequency and speed at which molecules cross the medium, thereby increasing the rate of diffusion.
4. Note that diffusion rate depends on factors like concentration gradient and temperature, so temperature does have an effect contrary to the idea that it has no effect.
5. Conclude that increasing temperature generally increases the diffusion rate because molecules move more rapidly, enhancing passive transport efficiency.