Question

Two chromatids of metaphase chromosome represents which of the following?

• A. Non-homologous chromosomes joined at centromere
• B. Maternal and paternal chromosome joined at centromere
• C. Replicated chromosomes to be separated at anaphase
• D. None of the above

Answer 1

Answer: (C)

Replicated chromosomes to be separated at anaphase

A normal cell cycle comprises of interphase (G${}_1$ phase, S phase and G${}_2$ phase) and M phase. During the S phase of interphase, the DNA duplicates due to replication. The duplication of DNA leads to the production of two chromatids joined at the centromere. The M phase comprises of prophase, metaphase, anaphase and telophase. The chromatin material coils into distinct structures called chromosomes in the prophase. In the metaphase stage, chromosomes are arranged at the equator. Each chromosome comprises of two sister chromatids (produced due to DNA synthesis in the S phase) joined at the centromere. In the anaphase stage, the centromere splits and the two sister chromatids move to opposite poles.

So, the correct answer is option C.