Questions: The most important biological contribution of carbon dioxide to the atmosphere is through a) microbial decomposition of dead material b) burning organic material c) respiration from the lungs

The answer is the first one (a): microbial decomposition of dead material.

Explanation for each option:

a) Microbial decomposition of dead material: This process is a significant biological contribution of carbon dioxide to the atmosphere. Microorganisms break down organic matter, releasing carbon dioxide as a byproduct. This is a natural and continuous process that plays a crucial role in the carbon cycle.

b) Burning organic material: While burning organic material does release carbon dioxide into the atmosphere, it is not primarily a biological process. It is more of a chemical process, often associated with human activities like burning fossil fuels or biomass.

c) Respiration from the lungs: Respiration is a biological process where organisms, including humans and animals, release carbon dioxide as a byproduct of converting oxygen and glucose into energy. While it contributes to atmospheric carbon dioxide, it is not as significant as microbial decomposition in terms of the overall carbon cycle.

In summary, microbial decomposition of dead material is the most important biological contribution of carbon dioxide to the atmosphere.