Put these events of earth’s history in the order that they happened: dominance of mammals, sharks and trilobites abundant in the oceans, dominance of reptiles, development of the ozone layer, plants and animals colonizing land.

When proteins are being produced by a cell, scientist say that the genes are question 2 options: activated turned off replicated deactivated

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons

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