Which is not a function of the cell membrane?

Helps substances pass from the cytoplasm into the nucleus
Keeps materials within the cell separated from the environment outside the cell
Helps control the movement of materials into and out of the cell
Allows the cell to change shape under pressure

The correct answer is A. Helps substances pass from the cytoplasm into the nucleus.

The cell membrane is a semipermeable membrane that allows certain substances to pass through while keeping others out. It is made up of a phospholipid bilayer, which is a double layer of phospholipid molecules. The phospholipid molecules have a hydrophilic head and a hydrophobic tail. The hydrophilic heads face the water inside and outside the cell, while the hydrophobic tails face each other in the middle of the membrane.

The cell membrane helps to keep materials within the cell separated from the environment outside the cell. It also helps to control the movement of materials into and out of the cell. This is done through a process called diffusion, which is the movement of molecules from an area of high concentration to an area of low concentration.

The cell membrane also allows the cell to change shape under pressure. This is because the phospholipid bilayer is fluid and can move around.

Option A is not a function of the cell membrane because the cell membrane does not help substances pass from the cytoplasm into the nucleus. The nucleus is surrounded by a nuclear envelope, which is a double membrane that separates the nucleus from the cytoplasm. The nuclear envelope has pores that allow certain molecules to pass through, but the cell membrane does not.