It would mean that the organisms rely on each other for survival.
Hope this helps (:
Answer is D.
Waste products from metabolism are carried by the circulation to the kidneys, which filter them out if the blood to be excreted in urine.
Create the greenhouse effect.
Answer:
a.Side with a lower consitration of squares.
b.Transport protien.
c.Energy imput from the cell.
d.Plasma membrain.
e.Side with a higher consitration of squares.
I think.