Question

the process of photosynthesis and respiration can be thought of as a cycle because the products of one are used as the raw materials of the other. both give off oxygen to be used by animals. one is used by plants and the other is used by animals. they both have the same purpose.

Explanation:

Photosynthesis in plants produces oxygen and glucose, which are used as raw - materials for respiration in animals and plants. Respiration produces carbon dioxide and water, which are used as raw - materials for photosynthesis. Thus, the products of one process are used as the raw materials of the other, forming a cycle.

Answer:

The products of one are used as the raw materials of the other.