Do Plants Have Cell Membranes?

All cells have cell membranes -- plant cells included. Unlike animal cells, plants also have an outer cell wall that provides tensile strength to counteract osmotic pressure. The cell wall, however, isn't usually considered a part of the cell membrane.

Features

• Plant cell membranes, like those of animal cells, are lipid bilayers -- double layers of molecules called phospholipids. These molecules have a polar group that can interact with water molecules and two nonpolar fatty acid tails that do not. The molecules self-assemble into a formation where the tails point inwards while the head groups point outwards towards the water on either side.

Function

• The main function of any cellular membrane is to regulate traffic into and out of the cell. Many particles like charged ions do not diffuse across cell membranes unless they are transported across by membrane-embedded proteins. The cell membrane also helps to confine the contents of the cell, like large proteins and other molecules.

Considerations

• One important difference between plant cell membranes and animal cell membranes is the absence of cholesterol. Animal cells use cholesterol to help stabilize cell membranes and provide them with greater fluidity. Plant cell membranes also incorporate sterols, but they do not have cholesterol.