Question

A student started a model to show the cycling of carbon Food>Cellular respiration>carbon dioxide.?
what should the student add to the model next?

Answer 1

Next step will be Carbon dioxide absorbed by the plants and oxygen is produced.

So, full circle will be Food > Cellular respiration > Carbon Dioxide > Absorbed by plants> Oxygen is produced.

Answer 2

Photosynthesis will happen next.

Photosynthesis is a process carried out by green plants to convert water, carbon dioxide and minerals into oxygen and energy rich organic compounds  in the presence of sunlight.

Here, it is given that

Food > Cellular respiration > Carbondioxide released

Food is the input and carbondioxide is the product of the process Cellular respiration.

Hence the complete model will be

Food > Cellular respiration > Carbondioxide released > Photosynthesis > Oxygen released + Food

Here carbondioxide is the input and food and oxygen are the products of the process photosynthesis.