Pine trees are part of the family Pinaceae. Sea urchins are from class <span>Echinoidea. These two organisms are very different in many ways. Pine trees have exposed seeds or sexually reproduce. They are coniferous. Sea urchins, well they don't produced seeds, they reproduce through external fertilization. Sea urchins are omnnivorous. </span>
A There are no surviving species if a mass extinction occurs
Answer:
cytoplasm
Explanation:
Both prokaryotic and eukaryotic cells have structures in common. All cells have a plasma membrane, ribosomes, cytoplasm and DNA... the cytyis all the contents of the cell inside the cell memey, not including the nucleus.
A protein may consist of as many as 5000 amino acid molecules.