MCQ on Cell Cycle and Cell Division   

MCQ on Cell Cycle and Cell Division

1. Which type of chromosomes segregate when a cell undergoes meiosis?

a) Homologous chromosomes

b) Non- homologous chromosomes

c) Both (a) and (b)

d) Centric and acentric chromosomes

2. Term ‘meiosis’ was proposed by

a) Farmer and Moore    
b) Flemming      
c) Strasburger   
d) Darlington

3. Meiosis can be observed in

a) tapetal cells

b) Megaspores

c) Micropores

d) Spore mother cells

4. Crossing over that result in genetic recombination in higher organisms occurs between

a) Sister chromatids of bivalent

b) Non-Sister chromatids of a bivalent

c) Two daughter nuclei

d) Two different bivalents

5. In which of the following stage of the cell cycle, the attachment of spindle fibres to kinetochores of chromosomes occurs?

a) Prophase       
b) Metaphase  
c) Anaphase      
d) Telophase

6. The sequence of events by which a cell duplicates its genome, synthesizes the other constituents of the cell and eventually divides into two daughter cells is termed as

a) Cell division  
b) Cell cycle       
c) Cell growth   
d) Cell duplication

7. In animal cell has, cytokinesis involves

a) The separation of sister chromatids

b) The contraction of the contractile ring of micro filament

c) Depolymerization of kinetochore microtubules

d) A protein kinase that phosphorylaes other enzymes

8. Which is correct for meiotic metaphase-I?

a) Bivalents are arranged at equator

b) Univalent are arranged at equator

c) Non-homologous chromosomes forms pair

d) Spindle fibres are attached at chromomere

9. Crossing over is the exchange of genetic material between

a) Non-sister chromatids of the homologous chromosomes

b) Sister chromatids of the homologous chromosome

c) Chromatids of non-homologous chromosomes

d) The genes those are completely linked

10. Which of the following phase of the cell cycle is not a part of interphase?

a) S        
b) M     
c) G₀     
d) G₁

11.         

Colchicine arrests which of the following stage of cell division?

a) Prophase       
b) Anaphase     
c) Telophase     
d) Metaphase

12. Select the correct option with respect to mitosis.

a) Chromatids start moving towards opposite poles in telophase

b) Golgi complex and endoplasmic reticulum are still visible at the end of prophase

c) Chromosomes move to the spindle equator and get aligned along equatorial plate in metaphase

d) Chromatids separate but remains in the centre of the cell in anaphase

13. Small disc-shaped structures at the surface of the centromeres that appear during metaphase are

a) Kinetochores
b) Metaphase plate       
c) Spindle fibres               
d) Chromatid

14. Cell division cannot be stopped in which phase of the cell cycle?

a) G₁-phase       
b) G₂-phase       
c) S-phase          
d) Prophase

15. Meiosis in AaBb will produce gametes

a) AB, aB, Ab, ab              
b) AB, ab             
c) Aa, bb              
d) Aa, Bb

16. The stage between two meiotic division is called

a) Interphase    
b) Cytokinesis   
c) Interkinesis   
d) Karyokinesis

17. If we ignore the effect of crossing over, how many different haploid cells arise by meiosis in a diploid cell having 2n=12?

a) 8        
b) 16     
c) 32      
d) 64

18. Which of the following CdKs and cyclins comes under G₁ check point?

a) CdK₄/ Cyclin D              
b) CdK₆/ Cyclin D              
c) Both (a) and (b)           
d) CdK₂/ Cyclin B

19.         

Crossing over occurs at

a) Single strand stage

b) Two strand stage

c) Four strand stage

d) Eight strand stage

20. Chromosome number can be doubled by using which of the following?

a) Indole acetic acid

b) GA

c) Zeatin

d) Colchicines

1              (a)

Homologous chromosomes segregate when a cell undergoes meiosis.

2              (a)

Meiosis is a reductional division, in which the chromosome number is reduced to half. It was proposed by Farmer and Moore. It is found only in diploid germ cells and is main cause of variations. During meiosis, four daughter cells are formed from one cell.

3              (d)

Meiosis is a reductional division, in which chromosome number is reduced to half, i.e, haploid. It is generally observed in sex cells, i.e., male and female gametes. In bryophyte or pteridophyte, meiosis occurs in generative cells like spore mother cells.

4              (b)

The process of crossing over takes place in pachytene stage of prophase-I of meiosis-I. In this process, some genes of two non-sister chromatids of a bivalent are exchanged.

5              (b)

Metaphase plate is the plane of alignment of the chromosomes at metaphase.

During metaphase, spindle fibres attach to kinetochores of chromosomes.

Chromosome are moved to spindle equator and get aligned along metaphase plate through spindle fibres to both poles

6              (b)

Cell cycle was described by Howard and Pelc in 1953. The sequence of events by which a cell duplicates its genome, synthesizes the other constituents of the cell and eventually divides into two daughter cells is termed as cell cycle

7              (b)

In animal cells, cytokinesis involves the contraction of the contractile ring of microfilaments.

8              (a)

In meiotic division metaphase-I spindle apparatus starts appearing and bivalents become attached to spindle through centromeres. Bivalents then appear in the form of an equatorial plate due to the movement known as ‘congression’.

9              (a)

Crossing over is a process that produces new combination of genes by interchanging of segments between nonl-sister chromatids of homologous chromosomes. It occurs between homologous chromosomes at four stranded stages during pachytene of prophase-I of meiosis-I.

10           (b)

The cell cycle is divided into two basic phases

Interphase and M-phase (mitotic phase). Interphase further divides into three phases:

G₁-phase, S-phase and G₂-phase

11           (d)

Colchicine prevents spindle formation, which occurs during metaphase stage of cell division.

13           (a)

Kinetochores serve as the sites of attachment of spindle fibres to the chromosomes that are moved into position at the centre of the cell.

14           (c)

Cell division cannot be stopped in S-phase. The S-phase is the synthesis phase, in which the cell synthesises a replica of its genome, i.e., DNA replication occurs which ultimately result in the duplication of chromosomal material.

15           (a)

As a result of meiosis, the gamete of AaBb will be AB, aB, Ab, ab.

16           (c)

The stage between two meiotic divisions is called interkinesis. It is generally short lived and is followed by prophase-II, a much simpler prophase than prophase-I of meiosis-I.

17           (d)

The number of different haploid cells arise by meiosis can be calculated by 2ⁿ where,

n=number of haploid chromosomes.

18           (c)

The cell cycle is controlled by enzymes like cyclin dependent kinases (CdKs). CdKs phosphorylate amino acids like serine and threonine which initiates or blocks the activities related to cell cycle. The other check points involved in cell cycle are

                G₁check point (Enter S or synthesis) is controlled by CdK₄/Cyclin D, CdK₆/Cyclin D

                G₂ check point (Enter M or maturation promoting factor) by is controlled CdK₂/cyclin B

                Metaphase check point is controlled by cyclin B degradation

19           (c)

During pachytene substage of prophase-I of meiosis, the chromosomes are tetravalent i.e., contain two chromatids with each chromosome arms. Crossing over during this substage, which involves the exchange of segments between the non-sister chromatid of homologues.

20           (d)

Colchicine treatment doubles the chromosome number.