During cellular respiration, every living thing in this food web uses ______ gas and releases ______ back into the environment.
a. carbon dioxide:oxygen
b. oxygen:carbon dioxide
c. carbon dioxide:hydrogen
d. carbon dioxide:water vapor
this is because oxygen atoms bind to the hydrocarbons from food (glucose etc.) during formation ATP (Kreb's cycle). Carbon dioxide is a basic waste product which is removed because it increases the acidity of the blood if build-up occurs.
