A eukaryotic cell that receives a "go-ahead" signal at the `G_(1)` checkpoint of the cell cycle will

Options

A. complete the cycle and divide.
B. move directly into the M phase.
C. move directly into the `G_(2)` phase
D. enter a resting stage.

Answer

To answer the question regarding what happens to a eukaryotic cell that receives a "go-ahead" signal at the G1 checkpoint of the cell cycle, we can break down the process step by step:

### Step 1: Understanding the Cell Cycle
The cell cycle consists of several phases: G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis). Each phase has specific functions and checkpoints to ensure proper cell division.

**Hint:** Remember that the cell cycle is a series of phases that a cell goes through to divide and replicate.

### Step 2: The Role of the G1 Checkpoint
The G1 checkpoint is crucial as it assesses whether the cell is ready to proceed to the next phase. If the cell receives a "go-ahead" signal at this checkpoint, it indicates that the cell is healthy and ready to divide.

**Hint:** The G1 checkpoint is like a quality control check before the cell commits to division.

### Step 3: Consequences of Receiving the Go-Ahead Signal
If the cell receives the go-ahead signal, it will not enter a resting state (G0 phase) but will instead continue through the cell cycle. This means it will proceed to the S phase, where DNA replication occurs.

**Hint:** The go-ahead signal is a green light for the cell to continue its journey through the cell cycle.

### Step 4: Progression Through the Cell Cycle
After the S phase, the cell will enter the G2 phase, where it prepares for mitosis. Finally, the cell will transition into the M phase, where actual cell division occurs.

**Hint:** Think of the cell cycle as a relay race, where each phase is a leg that the cell must complete before moving on to the next.

### Step 5: Conclusion
In conclusion, a eukaryotic cell that receives a "go-ahead" signal at the G1 checkpoint will complete the cell cycle and divide. It will proceed through the S phase, G2 phase, and then into the M phase.

**Final Answer:** A eukaryotic cell that receives a "go-ahead" signal at the G1 checkpoint of the cell cycle will complete the cell cycle and divide.

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