Why do molecules go back and forth across the cell membrane?

Fossils can only be formed when? if mud, silt or tar is in the area to preserve the fossil ierosion does not occur and allows the fossil to form oxygen and microorganisms cannot decay the bones the area is dry and does not contain mud or silt

Which of these is true for bacteria because they are prokaryotic cells? a. they can engulf body cells in order to make memory cells. b. they must invade viruses in order to reproduce. c. they are much larger than eukaryotic body cells. d. they can reproduce on their own outside of other cells.

Anurse is caring for a client who is learning how to take care of a newly created colostomy. when observing a return demonstration of the colostomy irrigation, the nurse evaluates that more teaching is required when the client carries out what procedure?