Explain the composition of triglyceride.
Triglycerides are lipids composed of glycerol and fatty acids. Glycerol is a trihydroxy propane, meaning it contains three hydroxyl groups. Fatty acids have a carboxyl group attached to an R group, which could be a methyl, ethyl, or higher number of -CH₂ groups (1 to 19 carbons).
In triglycerides, three fatty acids are esterified with glycerol. The fatty acids present can be either saturated (without double bonds) or unsaturated (with one or more C=C double bonds). Triglycerides are also called fats and oils depending on their melting points. Oils have lower melting points and remain liquid in winters.
Explanation
The textbook context clearly explains that triglycerides are formed when fatty acids are esterified with glycerol. The key points are: (1) Glycerol is trihydroxy propane, (2) Fatty acids have a carboxyl group attached to an R group with 1-19 carbons, (3) Triglycerides specifically have three fatty acids esterified to glycerol, and (4) They are classified as fats or oils based on melting point. The answer follows the NCERT pattern of defining components first, then explaining the bond formation (esterification), and finally mentioning the classification.