Waxes are

Options

A. Esters of fatty acids and alcohol other than glycerol
B. True fats
C. Lipids that contains proteins
D. Sterols

Answer

**Step-by-Step Solution:**

1. **Understanding Waxes**: Waxes are a type of biomolecule that fall under the category of lipids. They are typically long-chain fatty acids esterified to long-chain alcohols.

2. **Identifying Characteristics**: Waxes are characterized by their hydrophobic nature and are solid at room temperature. They serve various functions, including protection and waterproofing in plants and animals.

3. **Analyzing the Options**:
- **Option 1**: Esters of fatty acid and alcohol other than glycerol - This describes sphingolipids, which are indeed esters but not the primary definition of waxes.
- **Option 2**: True fats - True fats are triglycerides, which consist of glycerol and three fatty acids. While waxes are lipids, they are not classified as true fats.
- **Option 3**: Lipid that contains protein - This describes lipoproteins, which are complexes of lipids and proteins, not waxes.
- **Option 4**: Esterol - This term is not commonly used in the context of waxes.

4. **Conclusion**: Based on the definitions and characteristics, the most appropriate description of waxes is that they are esters of fatty acids and long-chain alcohols, which is closest to the first option.

**Final Answer**: Waxes are esters of fatty acids and alcohol other than glycerol.

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