Who divided cell cycle in four stages i.e.
` G_(1) , S, G_(2)` and M :-

Options

A. W. Flamming
B. Strass burger
C. Howard and Pelc
D. Farmer

Answer

To answer the question "Who divided the cell cycle into four stages: G1, S, G2, and M?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Cell Cycle**: The cell cycle is a series of phases that a cell goes through as it grows and divides. It is crucial for cell reproduction and involves several stages.

2. **Identifying the Stages**: The cell cycle is divided into four main stages:
- **G1 Phase (Gap 1)**: This is the first stage where the cell grows and prepares for DNA replication.
- **S Phase (Synthesis)**: In this stage, DNA synthesis occurs, resulting in the duplication of chromosomes.
- **G2 Phase (Gap 2)**: This is the second growth phase where the cell continues to grow and prepares for mitosis.
- **M Phase (Mitosis)**: This is the final stage where the cell divides into two daughter cells.

3. **Historical Context**: The division of the cell cycle into these four stages was not attributed to a single scientist, but rather to a group of researchers.

4. **Identifying the Correct Scientists**: The scientists credited with dividing the cell cycle into these four stages are Howard and Pell. They systematically categorized the phases based on cellular activities during the cycle.

5. **Conclusion**: Based on the historical contributions to the understanding of the cell cycle, the correct answer to the question is that Howard and Pell divided the cell cycle into four stages: G1, S, G2, and M.

### Final Answer:
The scientists who divided the cell cycle into four stages (G1, S, G2, and M) are Howard and Pell.

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