Fill in the blanks:
Histone protein synthesis takes place during `"________"` phase of cell cycle.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Cell Cycle:** The cell cycle consists of several phases, which include G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis). Each phase has specific activities and functions.

2. **Identifying the S Phase:** The S phase is specifically known as the synthesis phase. During this phase, DNA replication occurs, which is crucial for cell division.

3. **Histone Protein Function:** Histone proteins are essential for DNA packaging. They are positively charged proteins that bind to negatively charged DNA, helping to condense it into a compact structure.

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