Cellular
a. carbon dioxide is a product.
b. oxygen is reactant. carried out in animals.
c. photosynthesis oxygen is a product.
d. carbon dioxide is a reactant.
e. produces usable energy source
f. both chemical reaction carried out in plants.

A. Carbon dioxide is a product.

Explanation: During cellular respiration the body takes in oxygen and uses it and turns it into carbon dioxide and lets it out, thus carbon dioxide is a product.

1)

i))the process of preparing food by green plants in the presence of sunlight is called photosynthesis.

ii) leaf is the site for photosynthesis.

iii) it takes place as,

6h2o+6co2=c6h12o6+602