Question

define cell membrane​

Answer 1

Explanation:

The cell membrane, therefore, has two functions: first, to be a barrier keeping the constituents of the cell in and unwanted substances out and, second, to be a gate allowing transport into the cell of essential nutrients and movement from the cell of waste products.

Answer 2

Answer:

Cell membranes are composed primarily of fatty-acid-based lipids and proteins. Membrane lipids are principally of two types, phospholipids and sterols (generally cholesterol).They can also attach to the second type of protein, called the intrinsic proteins.

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