Answer:
d. all of the above are true.
Passive transport is the movement of substances across the membrane without the expenditure of cellular energy.
They teach us what happened in Earth before we arrived. For example, if we had never found any dinosaur fossils, we would have no idea what happened. Fossils show us ancient life and what it was like back then.
Please give me brainliest ^.^
The endocrine system releases hormones into the bloodstream, most of which are released by the pituitary gland
i believe that to be correct