Question 1

Which phase of the cell cycle is characterized by DNA replication?

Accepted Answer

The Synthesis phase (S phase) of interphase is characterized by DNA replication and synthesis of histone proteins, where the amount of DNA per cell doubles while the chromosome number remains the same.

Question 2

The enzyme recombinase is required during which stage of meiosis?

Accepted Answer

Recombinase is the enzyme involved in the process of crossing over between non-sister chromatids of homologous chromosomes, which takes place during the pachytene stage of prophase I in meiosis.

Question 3

During which phase of mitosis do chromosomes line up at the equator?

Accepted Answer

During metaphase, the morphology of chromosomes is most easily studied, and chromosomes are clearly visible under the microscope as they line up along the metaphase plate (equator).

Question 4

Cells in the quiescent stage (G0) do which of the following?

Accepted Answer

Cells in the quiescent stage (G0) remain metabolically active but do not proliferate unless called on to do so depending on the requirement of the organism, exiting the G1 phase.

Question 5

Synapsis occurs between:

Accepted Answer

Synapsis is the pairing of homologous chromosomes, which occurs during the zygotene stage of prophase I in meiosis, accompanied by the formation of a complex structure called the synaptonemal complex.

Cell Cycle and Cell Division — MP Board Class 11 Biology Important Questions & Revision Notes