Valves ensure blood flows toward your heart. Vein valves work to bring the blood that flowed down via arteries back up to your heart.
a) precipitation is balanced by evaporation
The answer is B.) animals at the end of the food chain would not get enough food to stay alive.
10) the cv is wrong; it should be the number of coats of nail polish she applies
11) the iv is wrong; it should be the amount of paperclips on each plane (so basically the weight of each plane)
Nucleic acid is the macromolecule that carries code for building our body.
