What percentage of earths history has included present day humans?

How energy flows through each level in this energy pyramid. is all the matter and energy from one level transferred to the next level?

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above

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.