Question

Why is the term "lipid bilayer" a good name for cell membrane?

Answer 1

Well, since it is made up of lipids...

Explanation:

The cell membrane has some parts which are called "lipid bilayers". These layers are small but thick layers, mostly composed of lipid molecules. There are two parts of the layer, one which is hydrophobic and non-polar (water-fearing), and one which is hydrophilic and polar (water-attractive). Water molecules may pass through the hydrophilic part but not through the hydrophobic part, as like dissolves like, a fundamental rule in chemistry.

The lipid bilayer is an impenetrable membrane, but not fully, as it only allows water and gases to pass through it, and keeping harmful chemicals and molecules outside the cell.

Source:

http://www.sparknotes.com/biology/cellstructure/cellmembranes/section1/