Question

which of the following best describes the structure of lipid bilayer?
select the correct answer below:
a double layer of phospholipids with the polar ends facing inwards.
a double layer of phospholipids with the polar ends facing outwards.
a double layer of cholesterol molecules with the polar ends facing inwards
a double layer of cholesterol molecules with the polar ends facing outwards

Explanation:

Lipid bilayer is mainly composed of phospholipids. Phospholipids have a polar head (hydrophilic) and non - polar tails (hydrophobic). In an aqueous environment (such as the cell's internal and external environment which is mostly water), the polar heads will face the aqueous environment (outwards) to interact with water molecules, and the non - polar tails will face inwards away from water. Cholesterol is not the main component for forming the basic structure of the lipid bilayer.

Answer:

B. A double layer of phospholipids with the polar ends facing outwards.