Nitrogen is a component of

Options

A. Proteins
B. Carbohydrates
C. Lipid
D. Polyphosphate.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which of the given options contains nitrogen as a component. The options provided are proteins, carbohydrates, lipids, and polyphosphate.

2. **Analyzing Proteins**:
- Proteins are made up of amino acids.
- The basic structure of an amino acid includes an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom, and a variable side chain (R group).
- Since the amino group contains nitrogen, we can conclude that nitrogen is a component of proteins.

3. **Analyzing Carbohydrates**:
- Carbohydrates are organic compounds made up of carbon, hydrogen, and oxygen.
- They include sugars and starches.
- Importantly, carbohydrates do not contain nitrogen in their structure, making this option incorrect.

4. **Analyzing Lipids**:
- Lipids, which include fats and oils, are primarily composed of carbon, hydrogen, and oxygen.
- Similar to carbohydrates, lipids do not contain nitrogen, so this option is also incorrect.

5. **Analyzing Polyphosphate**:
- Polyphosphate consists of chains of phosphate groups.
- The primary elements in polyphosphate are phosphorus and oxygen, and it does not contain nitrogen, making this option incorrect as well.

6. **Conclusion**: Based on the analysis, the only option that contains nitrogen is **proteins**. Therefore, the correct answer is proteins.

**Final Answer**: Nitrogen is a component of **proteins**.

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