Sequence that correctly describes the cell cycle is:-

Options

A. `to S to G_(2) to Karyokinesis to Cytokinensis to G_(1)to`
B. `to G_(1) to G_(2) to Karyokinesis to Cytokinensis to`
C. `to G_(1) to S to G_(2) to Cytokinesis to Karyokinesisto`
D. `to Cytokinensis to Karyokinesis to G_(1) to S to G_(2) to`

Answer

To correctly describe the sequence of the cell cycle, we can break it down into the following steps:

1. **M Phase (Karyokinesis and Cytokinesis)**: The cell cycle begins with the M phase, which includes karyokinesis (nuclear division) and cytokinesis (cytoplasmic division). Karyokinesis consists of four stages: prophase, metaphase, anaphase, and telophase. After karyokinesis, cytokinesis occurs, which divides the cytoplasm and results in two daughter cells.

2. **G0 Phase**: After cytokinesis, the cell may enter a resting state known as the G0 phase. In this phase, the cell is metabolically active but does not grow or divide. It is a quiescent stage where the cell waits for favorable conditions to re-enter the cell cycle.

3. **G1 Phase**: If the cell exits the G0 phase or if it skips G0, it enters the G1 phase. During this phase, the cell grows and synthesizes proteins and organelles necessary for DNA replication and cell division.

4. **S Phase (Synthesis Phase)**: Following G1, the cell enters the S phase, where DNA replication occurs. The chromosome number doubles as each chromosome is replicated to form sister chromatids.

5. **G2 Phase**: After the S phase, the cell enters the G2 phase. This phase is characterized by further growth and preparation for mitosis. The cell checks for DNA damage, ensures all organelles are present, and confirms that conditions are favorable for division.

6. **Return to M Phase**: If all conditions are met during the G2 phase, the cell will proceed back to the M phase, where karyokinesis and cytokinesis will occur again.

Based on this sequence, the correct order of the cell cycle is: **M Phase (Karyokinesis and Cytokinesis) → G0 Phase → G1 Phase → S Phase → G2 Phase**.