Interphase:
(1) Includes karyokinesis and cytokinesis

(2) Some time called resting phase, is the preparatory phase for division in which cell undergoes growth and DNA replication in an order

(3) Is the shortest phase in which biomolecules are synthesised very fast

(4) Includes 5% duration of the cell cycle

Which one is correct about S-phase (synthetic phase)?
I. It occurs between G1 and G2
II. It marks the period during which DNA replicates
III. At the end of this phase DNA is doubled but the number of chromosomes remains unchanged
IV. As the DNA is doubled in this phase number of chromosomes is also doubled
V. Centrioles replicate in this phase
VI. Amount of DNA changes from 2C to 4C
VII. It is pre G2 and post G1 phase
(1) I, II, IV, V, VI, VII are correct                 

(2) I, II, III, V, VI, VII are correct

(3) All are correct                                       

(4) Only IV is correct

The sequence of events by which a cell duplicates its genome, synthesises other constituents of cells and eventually divides into daughter cells is termed as:

1. Interphase                                   

2. M-phase

3. Karyokinesis + Cytokinesis             

4. Cell cycle

Which one is correct for G₀ stage?
I. It is a quiescent stage
II. In this phase cell cycle is stopped
III. G₀ cells in this stage do not grow or proliferate but metabolically active
IV. G₀ cells can divide in response to some stimulus
(1) All are correct                         

(2) I, II, III are correct

(3) I, II are correct                       

(4) Only I and IV are correct

Which of the following statements is false?
(1) Mitosis or the equational division is usually restricted to the 2N cells only

(2) In onion 2N = 16

(3) Growth and reproduction are characteristics of cells indeed of all living organism

(4) In plants meristematic tissues show meiosis

At metaphase of mitosis, each chromosome consists of _______ chromatid(s) _______ centromere(s) ________ kinetochore(s) and _______ molecules of DNA:

(1) 2, 1, 2, 2        

(2) 2, 2, 2, 2       

(3) 2, 1, 1, 1                  

(4) 2, 1, 2, 1

In human cells chromosomes are:

(1) Always condensed during the entire cell cycle

(2) Different in different tissues

(3) Of the same size and shape

(4) Visible only during mitosis and meiosis

In prophase mitosis, which one of the following events occurs in animal cells but not in plant cells?

(1) Centrioles migrate to opposite sides of the nucleus

(2) Homologous chromosomes do not associate

(3) The nuclear envelope (membrane) breaks down

(4) Nucleoli disappear

Synaptonemal complex is more conspicious at:

(1) Zygotene        

(2) Pachytene      

(3) Diplotene         

(4) Leptotene

Centrosomes are:

(1) Constricted regions of chromosomes

(2) Regions where microtubules polymerise

(3) Part of Cilia

(4) The central part of the same cell