Metaphase chromosome appears to be longitudinally divided into two identical parts known as

Options

A. Sister chromosomes
B. Satellites
C. Daughter chromsomes
D. Sister chromatids.

Answer

**Step-by-Step Solution:**

1. **Understanding Metaphase Chromosomes**: During metaphase, chromosomes are highly condensed and aligned at the cell's equatorial plane. Each chromosome consists of two identical halves.

2. **Identifying the Structure**: The two identical halves of a metaphase chromosome are known as chromatids. Specifically, they are referred to as sister chromatids because they are identical copies formed during DNA replication.

3. **Role of the Centromere**: The sister chromatids are joined together at a region called the centromere. This is the point where the two chromatids are attached and is crucial for the proper segregation of chromosomes during cell division.

4. **Division of Chromosomes**: During anaphase, the centromere divides, and the sister chromatids are pulled apart to opposite poles of the cell. After this separation, each chromatid is considered an individual chromosome.

5. **Correct Terminology**: The question asks for the term used to describe the two identical parts of a metaphase chromosome. The correct terms are "sister chromatids" and "daughter chromosomes" (after separation during anaphase).

6. **Conclusion**: Therefore, the answer to the question is that the metaphase chromosome appears to be longitudinally divided into two identical parts known as sister chromatids (which become daughter chromosomes post-separation).

**Final Answer**: The two identical parts of a metaphase chromosome are known as sister chromatids (and can also be referred to as daughter chromosomes after they separate).

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