The active phase, also called metabolic or energetic phase with most cytogenetic activity is

Options

A. lnterphase
B. M-Phase
C. Meiosis
D. Pachytene

Answer

To answer the question, "The active phase, also called metabolic or energetic phase with most cytogenetic activity is," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Cell Cycle**: The cell cycle is divided into two main phases: Interphase and M phase (mitotic phase). Interphase is where the cell spends most of its time.

2. **Identifying Interphase Components**: Interphase consists of three sub-phases:
- G1 phase (Gap 1): The cell grows and synthesizes proteins.
- S phase (Synthesis): DNA replication occurs, doubling the genetic material.
- G2 phase (Gap 2): The cell prepares for mitosis, continuing to grow and produce proteins.

3. **Recognizing the Characteristics of Interphase**: Interphase is characterized by high metabolic activity, where the cell performs essential functions, including growth, DNA replication, and preparation for division. This phase accounts for over 90% of the cell cycle.

4. **Comparing with M Phase**: The M phase includes mitosis (Prophase, Metaphase, Anaphase, Telophase) and cytokinesis, which is the actual division of the cell. This phase is much shorter compared to Interphase and is primarily focused on the separation of chromosomes.

5. **Evaluating Other Options**:
- Meiosis is a type of cell division that reduces chromosome number and is not the active phase referred to in the question.
- Pachytene is a stage in prophase I of meiosis and does not represent the overall active phase of the cell cycle.

6. **Conclusion**: Given that Interphase is the phase with the most cytogenetic activity and is described as the metabolic or energetic phase, the correct answer is Interphase.

### Final Answer:
The active phase, also called metabolic or energetic phase with most cytogenetic activity is **Interphase**.

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