Cells are the most simple level of organization, as tissues contain cells, organs contain tissues and systems contain organs, so R would be your answer.
<span>The answer is : movement, reproduction, obtaining food and oxygen, and body structure</span>
Possibility of acid rain will increase
I think b. Proteins are polymers of amino acids is the correct answer
I believe GUU would code for valine and and AAA would code for lysine.
