The portion of the cell membrane is responsible for the isolating function of the membrane, while the portion regulates exchange and communication with the environment

lipid; protein

Explanation:

The role of lipid portion is that the structural components of the membrane provide barrier to the other species in coming and going out through through the cell and marks boundaries of the cell.

The role of the protein portion is that the membrane receptor the proteins relay signals between the internal and the external environments of the cells. It transport the protein molecules across membrane. It regulates the communication and exchange with the environment.

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