Question

why do we require oxygen​

Answer 1

Answer:

we require oxygen to live in and survive in environment. Plants use carvondioxide and release oxygen which is then used by animals and other organisms.

Answer 2

Answer:

We breathe because oxygen is needed to burn the fuel [sugars and fatty acids] in our cells to produce energy.) ... (Oxygen is brought into the lungs via breathing, where it is transported by red blood cells to the entire body to be used to produce energy.