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 the drug colchicine affects cell division, we need to understand the role of the spindle apparatus and the specific stages of mitosis.

### Step-by-Step Solution:

1. **Understanding Mitosis**: Mitosis is the process by which a cell divides its nucleus and genetic material to form two daughter cells. It consists of several stages: prophase, metaphase, anaphase, and telophase.

2. **Role of the Spindle Apparatus**: The spindle apparatus is crucial for the separation of chromosomes during cell division. It is made up of microtubules that form from tubulin proteins. These microtubules attach to the chromosomes at their centromeres and help pull them apart to opposite poles of the cell.

3. **Effect of Colchicine**: Colchicine is a drug that disrupts the formation of microtubules by inhibiting tubulin polymerization. This means that if colchicine is present, the spindle fibers cannot form properly.

4. **Identifying the Affected Stage**:
- **Prophase**: The spindle apparatus begins to form, but the chromosomes have not yet aligned.
- **Metaphase**: The chromosomes are aligned at the metaphase plate, and the spindle fibers are fully formed and attached to the chromosomes.
- **Anaphase**: The sister chromatids are pulled apart towards opposite poles of the cell.
- **Telophase**: The chromosomes reach the poles, and the nuclear envelope begins to reform.

Since colchicine prevents the formation of spindle fibers, it will primarily affect the **metaphase** stage, where the spindle apparatus is essential for aligning and separating the chromosomes.

5. **Conclusion**: The correct answer is that colchicine will affect the **metaphase** stage of mitosis.

### Final Answer:
The stage of mitosis that will be affected by colchicine is **metaphase**.