Fact 1: Electron transport is the final stage of aerobic respiration.

Fact 2: Aerobic respiration is an oxidative process which uses oxygen as a final electron acceptor.

Given the two facts above, answer the question "What is oxygen used as in respiration?" with the following options: 
- heat produced
 - electron acceptor
 - photosynthesis
 - Chemical energy
 - preventing heat transfer
 - Veins and arteries.
 - it keeps an organism warm
 - It helps them survive


 

  electron acceptor       