What is something cells cannot survive without?
gas Air O2 CO2 Ca O3 Fe He
A B C D E F G H
And oxygen, O2, is the molecule to do it.
Cells cannot survive without O2.
What is something cells cannot survive without? (A) gas (B) Air (C) O2 (D) CO2 (E) Ca (F) O3 (G) Fe (H) He