A mouse cell is treated with a chemical that interferes with the activity of microfilaments. Which of the following will probably be affected the most ?

Options

A. Formation of spindle fibres
B. Division of cytoplasm
C. Chromosome duplication
D. Pairing of homologous chrmosomes

Answer

To solve the question regarding the effects of a chemical that interferes with the activity of microfilaments in a mouse cell, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Microfilaments**: Microfilaments are components of the cytoskeleton, primarily made up of actin and myosin proteins. They play crucial roles in various cellular functions, including maintaining cell shape, enabling cell movement, and facilitating cell division.

2. **Identify the Functions of Microfilaments**: Microfilaments are particularly important during cytokinesis, which is the process where the cytoplasm of a parental cell is divided into two daughter cells. They help in forming the contractile ring that leads to the separation of the two cells.

3. **Analyze the Options**:
- **Formation of Spindle Fibers**: This process is primarily facilitated by microtubules, not microfilaments. Therefore, this option is less likely to be affected.
- **Division of Cytoplasm**: This process, also known as cytokinesis, heavily relies on microfilaments to form the contractile ring that pinches the cell into two.
- **Chromosome Duplication**: This occurs during the S phase of the cell cycle and does not involve microfilaments. Thus, it will not be affected.
- **Pairing of Homologous Chromosomes**: This occurs during prophase I of meiosis and is not directly influenced by microfilaments, so it will also remain unaffected.

4. **Conclusion**: Given that the chemical interferes with microfilament activity, the process that will be affected the most is the **division of cytoplasm** (cytokinesis), as microfilaments are essential for this process.

### Final Answer:
The process that will probably be affected the most is the **division of cytoplasm**.

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