The dissolved oxygen content in water
Answer:
<h2> I don't know but my Answer is </h2><h3>from different environments ,each structure suits their environment better than the other's</h3>
I guess ribosomes are not present in leaf cells
I think that for 1 it’s either A or B as the kidneys and everything get air and the lungs release it.
For 2 is probably D as the others don’t really make much sense.