It is oberved that heart cells do not exhibit cell division. Such cells do not divide further and exit... Phase to enter an inactive stage called.... of cell cycle. Fill in the blanks

Explanation

To answer the question, we need to fill in the blanks regarding the cell cycle of heart cells.

1. **Understanding Cell Division**: Heart cells, like some other specialized cells, do not undergo cell division. This means they do not replicate or divide to form new cells.

2. **Identifying the Phase**: In the cell cycle, cells typically go through several phases: G1 (Gap 1), S (Synthesis), G2 (Gap 2), and M (Mitosis). The G1 phase is where the cell grows and prepares for DNA replication. Since heart cells do not divide, they exit this G1 phase.

3. **Inactive Stage**: After exiting the G1 phase, these cells enter an inactive stage. This stage is known as the G0 phase (or G-zero phase), where cells are in a quiescent state and do not actively participate in the cell cycle.

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