Question

understanding main ideas

1. describe the plasma membrane, and explain why it is called a bilayer structure.

Explanation:

The plasma membrane is composed of two layers of phospholipids. The hydrophilic heads face outward towards water - both inside and outside the cell, while the hydrophobic tails face inward away from water. This double - layer arrangement gives it the name bilayer structure. Phospholipids are amphipathic molecules with a polar head and non - polar tails. Cholesterol and proteins are also components of the plasma membrane. Cholesterol helps stabilize the membrane by preventing the fatty acid tails of phospholipids from sticking together.

Answer:

The plasma membrane is a structure composed mainly of two layers of phospholipids, along with cholesterol and proteins. It is called a bilayer because it consists of two layers of phospholipids, with the hydrophilic heads facing outward and the hydrophobic tails facing inward. Cholesterol helps to stabilize the membrane by preventing the sticking of fatty - acid tails of phospholipids.