Which specific protein is formed in `G_(2)-phase` ?

Options

A. Histone
B. DNA-polymerase
C. Scaffold proteins
D. Tubulin

Answer

**Step-by-Step Solution:**

1. **Understanding the G2 Phase**: The G2 phase, also known as the Gap 2 phase, is the third sub-phase of interphase in the cell cycle. It occurs after the S phase (where DNA is replicated) and before mitosis.

2. **Function of the G2 Phase**: During the G2 phase, the cell undergoes rapid growth and prepares for mitosis. This phase is characterized by significant protein synthesis, which is crucial for cell division.

3. **Identifying Protein Synthesis**: In the context of protein synthesis during the G2 phase, we need to identify which specific proteins are synthesized. The options provided are histone, DNA polymerase, scaffold proteins, and tubulin.

4. **Analyzing Each Option**:
- **Histone**: Histones are synthesized during the S phase, not the G2 phase. Therefore, this option is incorrect.
- **DNA Polymerase**: This enzyme is primarily involved in DNA replication, which occurs during the S phase, making this option incorrect as well.
- **Scaffold Proteins**: These proteins are not specifically synthesized during the G2 phase, so this option is also incorrect.
- **Tubulin**: Tubulin is a protein that forms microtubules, which are essential for cell division. Tubulin synthesis occurs during the G2 phase as the cell prepares for mitosis.

5. **Conclusion**: The specific protein formed in the G2 phase is **tubulin**. Therefore, the correct answer is option 4: tubulin.

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