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A membrane is a surface structure that encloses the cell and cell organelles.
The membranes include the cell membrane, tonoplasts, nuclei membrane, mitochondrial membrane and chloroplast membrane.
The membranes have a common basic structure which regulates the movement of materials in and out of the cells.
The cell membrane is made up of a phospholipid layer sandwiched by two protein layer (it is a lipoprotein layer) the overall thickness of the cell membrane is about 7.5 nm thick.
The membrane is perforated by small pores that allow the passage of substances in and out of the cells.
simiyu kelly answered the question on September 15, 2017 at 11:30
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