Fact 1: Cellular respiration is when a cell converts from oxygen and carbohydrates into carbon dioxide, water, and energy.

Fact 2: Cellular respiration involves a series of enzyme-mediated reactions.

Given the two facts above, answer the question "what is it when a cell converts from oxygen and carbohydrates into carbon dioxide, water, and energy?" with the following options: 
- A transportation fuel
 - extremely important
 - a hemisphere is tilted away from the sun
 - series of enzyme-mediated reactions
 - production of energy
 - the most widely used biofuel
 - chemical messengers
 - it helps plants in growing


 

    series of enzyme-mediated reactions     