Why do phospholipids form a bilayer in water?

A. The phosphate portions repel each other.

B. The hydrophilic and hydrophobic parts attract each other.

C. The phosphate portions attract water, and the lipid portions repel water.

D. The lipid portions attract water, and the phosphate portions repel water.

Answer: C. The phosphate portions attract water, and the lipid portions repel water.

Explanation: Every phospholipid molecule has two elements: the head (or the phosphate group), and two tails (two chains of fatty acids that lie side by side). The head is polar in nature, hence it is hydrophilic and carries a negative charge. This phosphate portion of the phospholipid molecule is attracted to water.

The chains of fatty acids (or the chains) are so placed to prevent them from coming into contact with water, as it is hydrophobic in nature. The bi-layer shields the tail and forms noncovalent bonds.

Physics

3 years ago

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