NEET 2026
- Exam
- NEET
- Year
- 2026
- Subject
- Biology
- Chapter
- Chapter
NEET 2026 · Biology · Chapter
Which of the following structural modifications in a simple...
Which of the following structural modifications in a simple triglyceride molecule leads to the formation of a compound lipid such as lecithin?
Options
- AReplacement of two fatty acid chains with four interconnected hydrocarbon rings.
- BReplacement of one fatty acid chain with a phosphate group linked to an organic compound.
- CSubstitution of the glycerol backbone with a complex long-chain amino alcohol.
- DAddition of a carbohydrate unit, such as galactose or glucose, to the glycerol backbone.
Correct answer
B. Replacement of one fatty acid chain with a phosphate group linked to an organic compound.
Step-by-step solution
A simple triglyceride consists of a glycerol backbone esterified with three fatty acid chains.
Lecithin is a type of phospholipid, specifically phosphatidylcholine. In phospholipids, one of the three fatty acid chains of a triglyceride is replaced by a phosphate group, which is further linked to a nitrogenous organic compound (choline in the case of lecithin).
The other options describe different classes of lipids: four interconnected hydrocarbon rings are characteristic of steroids, a long-chain amino alcohol backbone is found in sphingolipids, and the addition of a carbohydrate unit forms glycolipids.
Answer: Replacement of one fatty acid chain with a phosphate group linked to an organic compound.
Lecithin is a type of phospholipid, specifically phosphatidylcholine. In phospholipids, one of the three fatty acid chains of a triglyceride is replaced by a phosphate group, which is further linked to a nitrogenous organic compound (choline in the case of lecithin).
The other options describe different classes of lipids: four interconnected hydrocarbon rings are characteristic of steroids, a long-chain amino alcohol backbone is found in sphingolipids, and the addition of a carbohydrate unit forms glycolipids.
Answer: Replacement of one fatty acid chain with a phosphate group linked to an organic compound.