Cell becomes refractive and viscous first during

Options

A. prophase
B. telophase
C. anaphase
D. cytokinesis

Answer

### Step-by-Step Solution

1. **Understanding the Question**: The question asks during which phase of cell division the cell first becomes refractive and viscous.

2. **Identifying the Phases of Cell Division**: The main phases of mitosis are:
- Prophase
- Metaphase
- Anaphase
- Telophase
- Cytokinesis (though technically not a phase of mitosis, it is part of the cell division process)

3. **Analyzing Each Phase**:
- **Prophase**: This is the first phase of mitosis. During prophase, the chromatin condenses into visible chromosomes, the nuclear envelope begins to break down, and the cell prepares for division. Importantly, during this phase, the cell becomes spheroid, refractive, and viscous.
- **Metaphase**: In this phase, chromosomes align at the cell's equatorial plane, but there is no significant change in the cell's refractive or viscous properties.
- **Anaphase**: The sister chromatids are pulled apart to opposite poles of the cell. Again, there is no notable change in refractivity or viscosity.
- **Telophase**: The chromosomes reach the poles and begin to de-condense, and the nuclear envelope reforms. The changes in refractivity and viscosity are not prominent here.
- **Cytokinesis**: This is the process of cytoplasmic division following mitosis. The cell membrane constricts to form two daughter cells, but the initial changes in refractivity and viscosity occur earlier.

4. **Conclusion**: Based on the analysis, the cell becomes refractive and viscous first during prophase, which is the initial phase of mitosis.

### Final Answer: Prophase

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