Which substance is used to keep cells in metaphase stage of mitosis in blood culture technique

Options

A. Cholecystokinin
B. Chitin
C. Colchicine
D. Phytohaemoglobin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the specific substance used to keep cells in the metaphase stage of mitosis during blood culture techniques.

2. **Identifying the Substance**: The substance used for this purpose is known as colchicine. It is a compound that plays a crucial role in cell division.

3. **Function of Colchicine**: Colchicine acts as a mitotic inhibitor. It interferes with the normal function of the mitotic spindle, which is essential for the separation of chromosomes during cell division.

4. **Mechanism of Action**: Colchicine disrupts the formation of microtubules, which are necessary for the movement of chromosomes to opposite poles of the cell. By preventing the formation of these structures, colchicine effectively halts the cell cycle at the metaphase stage.

5. **Applications Beyond Blood Culture**: In addition to its use in blood culture techniques, colchicine is also utilized in cancer treatment. Since cancer cells divide uncontrollably, colchicine can inhibit their mitotic division, which is beneficial in managing cancer.

6. **Conclusion**: Therefore, the correct answer to the question is colchicine, which is used to keep cells in the metaphase stage of mitosis in blood culture techniques.

**Final Answer**: Colchicine.

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