Heparin is formed by

Options

A. (a) Liver cells
B. (b) Plasma cells
C. (c) Blood cells
D. (d) Spleen cells

Answer

**Step-by-Step Solution:**

1. **Understanding Heparin**: Heparin is a naturally occurring substance in the body that acts as an anticoagulant, meaning it helps prevent the formation of blood clots.

2. **Chemical Structure**: Heparin is classified as a glycosaminoglycan, which is a type of long unbranched polysaccharide.

3. **Production of Heparin**: The primary site of heparin production is the liver, specifically by liver cells known as hepatocytes. This is a key point because it directly answers the question regarding where heparin is formed.

4. **Other Sources**: While the majority of heparin is produced in the liver, it is also produced in smaller amounts by certain blood cells, specifically mast cells and basophils. However, these are not the main source of heparin.

5. **Evaluating Options**:
- Option A: Liver cells (hepatocytes) - This is the correct answer as it is the primary site of heparin production.
- Option B: Plasma cells - This is incorrect; plasma cells are involved in producing antibodies, not heparin.
- Option C: Blood cells - This is partially correct since mast cells and basophils (types of blood cells) do produce some heparin, but it is not the major source.
- Option D: Spleen cells - This is incorrect; spleen cells do not produce heparin.

6. **Conclusion**: The most appropriate answer to the question "Heparin is formed by" is **liver cells (hepatocytes)**.

**Final Answer**: Heparin is formed by liver cells (hepatocytes).

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