Question

a cell membrane regulates the direction of movement for substances in order to

Answer 1

In simple diffusion, small molecules without charges such as oxygen and carbon dioxide flow through a plasma membrane without assistance and without expending energy. Othersubstances such as proteins, glucose and charged particles called ions cannot pass through the selectively permeable membrane.

Answer 2

The cell membrane is selectively permeable to ions and organic molecules andcontrols the movement of substancesin and out of cells.