Diffusion：練習題

Which set of conditions would result in the shortest time for a substance to diffuse from one point to another?

A student investigates how temperature affects the rate of diffusion of potassium manganate(VII) crystals in water. Which graph correctly shows the relationship between temperature and the rate of diffusion?

In which of the following scenarios is the rate of diffusion least efficient for a cell?

The exchange of oxygen from the alveoli into the blood, and carbon dioxide from the blood into the alveoli, occurs primarily by which process?

In living organisms, the rate of diffusion can be influenced by several factors. Which of the following modifications to a cell's structure would most effectively increase the rate of gas exchange via diffusion?

Describe the biological importance of solutes moving by the process of diffusion in a living organism.

Explain how increasing the surface area-to-volume ratio affects the efficiency of diffusion in a biological system.

Certain medical conditions can lead to swelling in tissues due to fluid accumulation (edema). Relate this phenomenon to the principles of diffusion and osmosis, specifically concerning the movement of water and solutes between blood capillaries and the surrounding tissue fluid.

Diffusion is a vital process for the survival of many organisms.
(a) Explain what is meant by the term net movement in the context of diffusion.
(b) List two substances that must diffuse into a plant cell for it to stay alive and grow.

The rate of diffusion is influenced by the steepness of the concentration gradient.
(a) State the relationship between the concentration gradient and the rate of diffusion.
(b) In a leaf during the daytime, carbon dioxide is constantly being used up. Explain how this internal consumption of carbon dioxide helps the plant maintain a steady intake of the gas from the atmosphere.