A phosphoglyceride is always made up of

Options

A. a saturated or unsaturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached
B. a saturated or unsaturated fatty acid esterified to a phosphate group which is also attached to a glycerol molecule
C. only a saturated fatty acid esterified to a glycerol molecule to which a phosphate group is also attached
D. only an unsaturated fatty acid ester- ified to a glycerol molecule to which a phosphate group is also attached

Answer

**Step-by-Step Solution:**

1. **Understanding Phosphoglycerides**: Phosphoglycerides, also known as phospholipids, are essential components of cell membranes. They consist of a glycerol backbone, two fatty acid chains, and a phosphate group.

2. **Components of Phosphoglycerides**:
- **Glycerol**: This is a three-carbon molecule (C3H8O3) that serves as the backbone for phosphoglycerides.
- **Fatty Acids**: There are two fatty acid chains attached to the glycerol. These can be either saturated (no double bonds) or unsaturated (one or more double bonds).
- **Phosphate Group**: A phosphate group is attached to the third carbon of the glycerol molecule.

3. **Esterification Process**: The fatty acids are attached to the glycerol through a process called esterification, where the hydroxyl groups of the glycerol react with the carboxyl groups of the fatty acids, releasing water.

4. **Analyzing the Options**:
- **Option A**: "A saturated and unsaturated fatty acid is esterified to a glycerol molecule to which a phosphate group is attached." This is correct because phosphoglycerides can contain both types of fatty acids.
- **Option B**: "A saturated and unsaturated fatty acid is esterified to a phosphate group which is also attached to a glycerol molecule." This is incorrect because fatty acids are not esterified to the phosphate group.
- **Option C**: "Only a saturated fatty acid is esterified to a glycerol molecule to which a phosphate group is also attached." This is incorrect because phosphoglycerides can also contain unsaturated fatty acids.
- **Option D**: "Only an unsaturated fatty acid is esterified to a glycerol molecule to which a phosphate group is also attached." This is also incorrect for the same reason as option C.

5. **Conclusion**: The correct answer is **Option A**.

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