Question

what molecules do plants need for photosynthesis? how do they get these molecules? what molecules does your body need to do cellular respiration? how does your body get those molecules?

Explanation:

Plants need carbon - dioxide and water for photosynthesis. They get carbon - dioxide from the air through stomata and water from the soil via roots. The body needs glucose and oxygen for cellular respiration. Glucose is obtained from the digestion of food and oxygen is taken in through breathing.

Answer:

For plants in photosynthesis: Molecules needed are carbon - dioxide and water. They get carbon - dioxide from the air and water from the soil.
For the body in cellular respiration: Molecules needed are glucose and oxygen. Glucose is from food digestion and oxygen is from breathing.