The cells in our bodies are made up primarily of which four elements?

carbon, hydrogen, oxygen and nitrogen

Explanation:

1)Biotic factors are the living components of an ecosystem. These include living animals, plants, and microscopic organisms like bacteria. 
Abiotic factors are the non-living components of an ecosystem. ... Biotic and abiotic factors both influence each other.
2)Both biotic and abiotic factors are related to each other in an ecosystem, and if one factor is changed or removed, it can affect the entire ecosystem. Abiotic factors are especially important because they directly affect how organisms survive.