The following cell, undergoing mitosis, is at:

    

1.	Early prophase
2.	Late prophase
3.	Transition to metaphase
4.	Early metaphase

Anaphase promoting complex (APC) is a protein degradation machinery necessary for proper mitosis of animal cells. If APC is defective in a human cell, which of the following is expected to occur?

DNA replication in bacteria occurs

(1) during S-phase

(2) within nucleolus

(3) prior to fission 

(4) just before transcription 

Which of the following options gives the correct sequences of events during mitosis?

During cell growth, DNA synthesis takes place in

1. S-phase                       
2. ${\mathrm{G}}_1$-phase
3. ${\mathrm{G}}_2$-phase                     
4. M-phase 

When cell has stalled DNA replication fork, which checkpoint should be predominantly activated?

(1) G₁/s

(2) G₂/M

(3) M

(4) Both G₂/M and M

A cell at telophase stage is observed by a student in a plant brought from the field. He tells his teacher that his cell is not like other cells at telophase stage. There is no formation of cell plate and thus the cell is containing more number of chromosomes as compared to other dividing cells. This would result in

(1) polyploidy

(2) somaclonal variation

(3) polyteny

(4) aneuploidy

Which of the following is not a characteristic feature during mitosis in somatic cells
1. Disappearance of nucleolus

2. Chromosome movement

3. Synapsis

4. Spindle fibres

Spindle fibres attach on to 

In meiosis crossing over is initiated at 

1. leptotene

2. Zygotene

3. diplotene

4. pachytene