The inside of a membrane bilayer is

The correct answer will be - hydrophobic

Explanation:

The plasma membrane of a cell is composed of lipids commonly called phospholipids.

The phospholipid structure contains a hydrophilic head and a hydrophobic tail. The phospholipids in a plasma membrane are arranged in two layers called bilayer.

Bilayer contains the hydrophilic head faces the external environment whereas the hydrophobic tail composed of fatty acids is present inside and provide hydrophobic character to the layer.

Thus, inside the membrane is hydrophobic.

hydrophobic

Explanation:

the hydrophobic ends which is "water fearing" faces inwards so that it does not interact with the water or liquid outside the membrane