Question

which pathway adds carbon dioxide back to the atmosphere from living organisms? feeding aerobic cellular respiration photosynthesis by plants and algae fossilization

Explanation:

Aerobic cellular respiration is a metabolic process in which living organisms (including animals, plants, fungi, and many bacteria) break down glucose (or other organic molecules) in the presence of oxygen. The chemical equation for aerobic cellular respiration is \(C_6H_{12}O_6+6O_2
ightarrow6CO_2 + 6H_2O+\text{energy}\). As we can see from the equation, carbon - dioxide (\(CO_2\)) is a by - product of this process and is released back into the atmosphere.

Feeding is a process related to the transfer of organic matter (and thus carbon in the form of organic compounds) from one organism to another in a food chain or food web, but it does not directly add \(CO_2\) to the atmosphere.

Photosynthesis by plants and algae is the process of taking in \(CO_2\) from the atmosphere (along with water) and using sunlight to convert it into glucose (\(C_6H_{12}O_6\)) and oxygen (\(O_2\)). The equation is \(6CO_2+6H_2O
ightarrow C_6H_{12}O_6 + 6O_2\), so it removes \(CO_2\) from the atmosphere.

Fossilization is a long - term geological process where dead organisms are transformed into fossils over millions of years. This process sequesters carbon in the Earth's crust rather than adding \(CO_2\) to the atmosphere.

Answer:

Aerobic cellular respiration.