Your body used the respiratory system (lungs)
Easy. Answer is oxygen because it says which one was missing before any life was on earth. And in order to have life on earth you need oxygen!
:)
Answer:
Hypertonic
Explanation:
In hyper-tonic solutions, the cell will shrink and crenate. The mass and volume of a gummy bear that is placed in a salt solution will decrease due to the effect of osmosis. When placed in water, a hypo-tonic solution, the gummy bear will expand in size and volume due to the water entering it.
Answer:
DNA to RNA to protein
Explanation:
It states that <em>genes</em> specify the sequence of m<em>RNA</em> molecules, which in turn specify the sequence of <em>proteins.</em>
Melting of ice and island decreasing in level