<span>The body needs oxygen for cellular respiration. When doing strenuous activity, such as lifting weights, the mitochondria cannot get enough oxygen. Without oxygen to act as an electron receptor, the body creates lactic acid to "reset" coenzymes to continue respiration.</span>
We all need to work together, I think is one. Can't really think of another example though.. sorry
Cell division is when a cell under goes mitosis. Which divides in top to create another cell of the same kind.
In Gamete a haploid germ of either sex unites with the opposite sex to have sex and have a zygote.
