Question

The given figure is a schematic break-up of the phases/stages of cell cycle. Select the correct option regarding it.

• A. 'a' represents karyokinesis which is the division of cytoplasm.
• B. 'b' is telophase which is just reverse of prophase.
• C. 'c' is the best phase to count total number of chromosomes in any species.
• D. In 'd' stage, replication of DNA takes place on the template of the existing DNA.

Answer 1

The correct option is D In 'd' stage, replication of DNA takes place on the template of the existing DNA.

The cell cycle is the series of growth and developmental steps of a cell which initiates from the birth of a cell by dividing from the mother cell (parental cell) and giving rise to new daughter cells. To divide a cell must go through this stages-it must grow, copy its genetic material that is DNA, and physically split into two daughter cells. The cell performs all this tasks in an organized cyclical pathway and at the end of each go-round the two daughter cell can start the exact same process over again from beginning. This includes Interphase and mitotic phase. Interphase includes G1 phase( where the cell grows physically larger,copies organelles and makes molecular building blocks it will need in later steps), S phase is the synthetic phase in which the cell synthesizes a complete copy of the DNA in its nucleus. G2 phase is the second gap phase where the cell develops itself more and it ends when mitosis begins.During M phase (mitotic phase) the cell divides its copied DNA and cytoplasm to make two new cells.

So, the correct option is (D).