Are responsible for the transport of substances down a concentration gradient during facilitated diffusion.

Multicellular organisms use cell division, mitosis, for growth and the maintenance and repair of cells and tissues. single-celled organisms may use cell division as their method of reproduction. regardless of the reason for mitosis, the process ensures genetic continuity. what is the step in the cell cycle that ensure genetic continuity?

Nucleic acids offer variability because they contain alternate forms of genes called .

Produce proteins by following coded instructions that come from the nucleus of the cell.