Question

Because the final stages of cellular respiration require oxygen the are said to be

Answer 1

The word that describes a process that can only happen in the presence of Oxygen (such as the final stage of respiration, the <em />Electron Transport Chain) is Aerobic.

Conversely, if a process does not require the presence of Oxygen (such as glycolysis, the first stage of respiration) we can say that it is anaerobic.