Diffusion is an important process in animals and plants. The movement of many substances into and out of cells occurs by diffusion.
Describe why diffusion is important to animals and plants.
In your answer you should refer to:
• animals
• plants
• examples of the diffusion of named substances.

Diffusion helps animals in respiration. The cells in an animal's body need glucose and oxygen for respiration. Both these are carried in the blood. When blood reaches the cells the molecules of glucose and oxygen diffuse out of the blood and into the cells. As cells use up the glucose and oxygen they produce waste chemicals and carbon dioxide.

Diffusion is a very important process for photosynthesis where carbon dioxide from the stomata diffuses into the leaves and finally into the cells. This helps the plants to photosynthesize and produce more food.

Example for animals: Animals using glucose and oxygen in diffusion.

Examples for plants: Plants using carbon dioxide to photosynthesize.

answer: b: experiments that showed that all cells are similar in how they metabolize and in their composition

explanation: