Answer:
generic variation helps species survive because it gives there offspring there traits to survive
Explanation:
Valves ensure blood flows toward your heart. Vein valves work to bring the blood that flowed down via arteries back up to your heart.
I think a fossil? Thats my guess.
E. coli cells are found in the kingdom and domain of bacteria. They are unicellular, microorganisms that are single celled and shaped like rods
