Question

Differentiated cells are

• A. Premitotic specialised.
• B. Post-mitotic specialised.
• C. Premeiotic specialised.
• D. Post-meiotic specialised.

Answer 1

The correct option is B Post-mitotic specialised.

A typical cell cycle comprises of interphase and mitotic phase (M phase). The interphase comprises of first growth phase or $G_1$ phase, synthesis phase or S phase and second growth phase or $G_2$ phase. The DNA synthesis occurs during S phase in the process of DNA replication. The S phase is followed by $G_2$ phase, after which the cell enters mitotic phase. The G1 phase starts immediately after the mitotic phase and leads to the S phase. Hence, $G_1$ is also called the post mitotic phase. It is during $G_1$phase that cell prepares for DNA replication and synthesis of DNA. The G1 phase is the phase for active protein synthesis. Various species of RNA, all the enzyme machinery and other proteins required for DNA replication are synthesized during $G_1$ ase.

So, the correct answer is option B.