Lecithin is a

Options

A. Fatty acid
B. Phospholipid with choline attached to phosphate group
C. Cholesterol
D. fat

Answer

To determine what lecithin is, we can analyze the options provided in the question step by step.

### Step 1: Understand the Structure of Lecithin
Lecithin is a type of molecule that is found in cell membranes. It is composed of several components:
- Glycerol
- Two fatty acid chains
- A phosphate group
- A choline molecule attached to the phosphate group

### Step 2: Analyze the Options
Now, let's look at the options given in the question:
1. Fatty acid
2. Phospholipid with choline attached to the phosphate group
3. Cholesterol
4. Fat

### Step 3: Identify the Correct Option
- **Option 1 (Fatty acid)**: Lecithin is not just a fatty acid; it is a more complex structure.
- **Option 2 (Phospholipid with choline attached to the phosphate group)**: This accurately describes lecithin, as it contains a phosphate group and is indeed a phospholipid.
- **Option 3 (Cholesterol)**: Lecithin is not cholesterol; they are different types of biomolecules.
- **Option 4 (Fat)**: While lecithin contains fatty acids, it is not classified simply as fat.

### Conclusion
The correct answer is **Option 2: Phospholipid with choline attached to the phosphate group**.

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