In the fossil record, there is no evidence of anything living on land before plants. why are plants necessary before more complicated animals can evolve?
a. plants were needed to produce oxygen.
b. plants were not needed.
c. plants were needed to change the soil content.
d. plants were needed to produce carbon dioxide.

What happens as electrons move along the chain of molecules known as the electron transport chain? they gain energy, which causes atp molecules to lose phosphate groups. they gain energy, which causes h *ions to join with oxygen to produce water. they lose energy, which is then used by the cell to make atp. they lose energy, which is then used to break down atp.