Question

entry of only certain substance into and out of the cell​

Answer 1

Answer:

The plasma membrane is a structure that forms a barrier between the cytoplasminside the cell and the environment outside the cell. It allows only certain substances to pass in or out of the cell. The plasma membrane is composed mainly of a bilayer of phospholipid molecules

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Answer 2

Answer: Substances move in and out of cells by diffusion down a concentration gradient, through a partially permeable membrane.Plasma membrane is a structure that forms a barrier between the cytoplasm inside the cell and the environment outside the cell.It allows only certain substances to pass in or out of the cell.

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