If cells in the process of dividing are subjected to colchicine, a drug that interfere with the functioning of spindle apparatus, at which stage mitosis will affected ?

Options

A. Anaphase
B. Telophase
C. Interphase
D. Metaphase

Answer

To determine at which stage of mitosis colchicine affects the process of cell division, we need to analyze the role of colchicine and the spindle apparatus in mitosis.

### Step-by-Step Solution:

1. **Understanding Colchicine**: Colchicine is a drug that interferes with the formation of microtubules. Microtubules are essential components of the spindle apparatus, which is crucial for proper chromosome segregation during mitosis.

2. **Role of Spindle Apparatus**: The spindle apparatus is responsible for pulling the chromosomes apart during cell division. It consists of microtubules that connect to the centromeres of chromosomes and help in their alignment and separation.

3. **Identifying the Stages of Mitosis**: Mitosis consists of several stages: prophase, metaphase, anaphase, and telophase. The spindle apparatus is most active during metaphase and anaphase, where it plays a critical role in aligning and separating the chromosomes.

4. **Effect of Colchicine on Mitosis**: Since colchicine inhibits the formation of microtubules by interfering with tubulin (the protein that makes up microtubules), it will primarily affect the stages of mitosis where the spindle apparatus is actively functioning.

5. **Determining the Affected Stage**: The most critical stage affected by colchicine is metaphase. During metaphase, chromosomes are aligned at the metaphase plate, and the spindle fibers are attached to the centromeres. If colchicine prevents the formation of these spindle fibers, the chromosomes cannot be properly aligned or separated.

6. **Conclusion**: Therefore, the stage of mitosis that will be affected by colchicine is **metaphase**.

### Final Answer:
Colchicine affects the **metaphase** stage of mitosis.

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