Fact 1: Oxygen is essential for cellular respiration for all aerobic organisms.

Fact 2: Oxygen, for example, is produced by plants.

Given the two facts above, answer the question "What is essential for cellular respiration for all aerobic organisms." with the following options: 
- electron
 - glucose
 - Energy
 - Energy.
 - chemicals
 - Plants
 - fungi
 - bacteria


 

      Plants   