Biology : Cell Cycle and Cell Division

DNA/chromosome replication takes place during:

• G₁- phase

• G₂- phase

• S- phase

• Prophase

In the hexaploid wheat, the haploid (n) and basic (x) numbers of chromosomes are

• n = 7  and x = 21

• n = 21 and x = 21

• n = 21  and x = 14

• n = 21  and x = 14

Spindle chromosomes have

• centriole

• kinetochore

• chromocentre

• chromomere

In mitotic cell division, the division of centromere and the division of chromatid occurs between

• anaphase and telophase

• prophase and metaphase

• telophase and interphase

• anaphase and metaphase

In which stage of the first meiotic division, each chromosome undergoes longitudinal division to give rise to two sister chromatids ? 

• Zygotene

• Diplotene

• Diakinesis

• Pachytene

The stage of cell cycle when cell has undergone differentiation is :

• G₀

• G₁

• G₃

• G₄

The importance of meiosis lies in :

• bringing discontinuous variations

• addition in the number of chromosomes

• reduction in the number of chromosomes

• maintaining the number of chromosomes

At what stage of the cell cycle are histone proteins synthesized in a eukaryotic cell?

• During entire prophase

• During telophase

• During S-phase

• During G₂ stage of prophase

What would be the number of chromosomes in the cells of the aleurone layer in a plant species with 8 chromosomes in its synergids?

• 16

• 24

• 32

• 32

The S-phase of cell cycle is characterized by:

• duplication of chromosome

• shotening of chromosome

• duplication of DNA

• duplicatin of centriole