Question

why do ee require oxygen

Answer 1

For respiration.. Cos the inhaled O2 is transferred to each and every cell where it is used for respiration via glycolysis and kreb's cycle to break down food supplements into ATP or energy

Answer 2

oxygen is brought into the lungs via breathing, where it is transported by RBC cell to entire body to be used to produce energy. we breath with the help of oxygen.
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