Antigens may be large molecules of

Options

A. proteins
B. carbohydrates
C. lipoproteins
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding Antigens**: Antigens are substances that can induce an immune response in the body. They are typically large molecules that are recognized by the immune system.

2. **Types of Antigens**: Antigens can come in various forms, including:
- Bacteria
- Viruses
- Other microorganisms

3. **Analyzing the Options**:
- **Option A: Proteins**: Antigens can indeed be large molecules of proteins. Proteins have complex structures and are a common type of antigen.
- **Option B: Carbohydrates**: Antigens may also be large molecules of carbohydrates. The surface of many pathogens has carbohydrate components that can act as antigens.
- **Option C: Lipoproteins**: Lipoproteins, which are complexes of lipids and proteins, can also serve as antigens. This means that antigens can include both lipid and protein components.

4. **Conclusion**: Since antigens can be made up of proteins, carbohydrates, and lipoproteins, the correct answer is **Option D: All of these**. This option encompasses all the types of molecules that can function as antigens.

**Final Answer**: Antigens may be large molecules of proteins, carbohydrates, and lipoproteins. Therefore, the correct answer is **D: All of these**.

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