SSCE/ WASSCE/NOVDEC Past Questions and Answers on Cell Cycle and Cell Division

 SSCE/WASSCE/GCE PASS QUESTIONS AND ANSWERS

OBJECTIVES

1.      During cell division, the two strands of chromosomes are joined at a point called
A. spindle             
B. chromatid       
C. centromere   
D. aster





2.      What stage during cell division is represented in the figure above?
A. Prophase                
B. Metaphase     
C. Anaphase        
D. Telophase

3.      During binary fission in lower organisms, the nucleus is known to undergo
A. mitosis            
B. meiosis         
C. fragmentation    
D. mutation

4.      One of the ways which body cells differ from gamete cells is in the
A. type of centromeres they contain
B. number of chromosomes pairs they contain
C. type of chromatide they contain
D. number of chromosomes they contain

5.    Homologous pairs of chromosomes separate during
A. Cytolysis              
B. Cleavage          
C. Mitosis    
D. Meiosis

6.    what stage mitotic division is represented in the diagram of the cell illustrated above
A. Prophase               
B. Telophase         
C. Anaphase    
D. Metaphase  

7.    This stage of mitosis is characterized by the
A. movement of the chromosome to the poles
B. arrangement of chromosomes on the equitorial planes
C. centromeres moving apart along the spindle
D. condensation of chromosomes and formation of spindles

8.    At which of the following stages of cell division can the cell be said to be resting
A. Anaphase              
B. Telophase      
C. Prophase         
D. interphase

9.    All hereditary characters in a cell are passed on from parent-cell to daughter-cell through the process of
A. mitosis              
B. meiosis        
C. fertilization       
D. implantation

10.        Which of the following statements about mitosis is false?
A. four daughter cell are produced
B. chiamata are not formed
C. bivalent are not formed            
D. the process does not lead to variation

11.        DNA replication occurs in a cell during
A. interphase of mitosis  
B. metaphase of meiosis
C. anaphase of meiosis
D. prophase of mitosis

12.        At the end of mitosis, the number of cells produced from a parent cell is
A. four                    
B. six            
C. eight         
D. two

13.        At which of the following stages of mitosis do the two daughter chromosomes separate completely?
A. Early prophase       
B. Telophase           
C. Anaphase    
D. Late prophase

14.     Which of the following cells in mammals do not normally undergo cell division?
A. cells of cornified layer
B. cells of germinal epithelium
C. epithelial cells of the cheek
D. cells of the 


15.      The stage of mitosis represented in the      diagram is  known as the
A. telophase              
B. metaphase      
C. anaphase      
D. interphase

16.        ln which of the following structures will cells undergoing meiosis be seen?
A. at the apices of stem and root
B. in the cortex of the stem
C. in the palisade mesophyll of the leaf
D. in the ovary of a flower

17.        The process of cell division by meiosis takes place only in
A. skin cells        
B. red bone marrow   
C. reproductive organs   
 D. lymphocytes

18.        Separation of sister chromatids during meiosis occurs in
A. metaphase II                
B. anaphase II             
C. prophase II        
D. telophase II

19.        Meiosis is important because it
A. maintains the number of chromosomes in successive generations

B. is the means asexual reproduction in flowering plants
C. ensures that the two daughter cells are genetically identical
D. brings about growth in multicellular organisms

20.        Meiosis take place
A. during growth and development
B. during gamete formation
C. during asexual reproduction
D. in somatic cells

Answers

1. C

6. A

11. A

16. D

2. C

7. D

12. D

17. C

3. A

8. D

13. C

18. B

4. D

9. A

14. A

19. A

5. D

10. A

15. A

20. B


THEORY

1.      (SSCE, 1994 Q2) (b) (i) Gives five features that distinguish between the two types of cell division that occur in the mammalian body.
(ii) What is the significant of each type of cell division?

Solution

(i) Five differences between mitosis and meiosisR

efer to blog content

2.      (SSCE, 1997 Q2) (a) What do you understand by each of the following terms (i) mitosis     (ii) meiosis

(b) (i) State two processes which occur in meiosis but not in mitosis.

(ii) Mention two ways in which meiosis is significant.

Solution

(i) Mitosis is the division of a cell to form two daughter cell contains the same number of chromosomes as the mother cells. It occurs in body or somatic.

(ii) Meiosis is a reduction division of a cell, which occurs within reproductive organs. It gives four gametes or spores with each having half the chromosome number of the parent.

(b) The following process occur only in meiosis· Formation of chiasmata

·         Pairing of homologous chromosome occurs in meiosis

·         There is separation of chromatids in meiosis whereas chromosome separation occurs in mitosis.

·         Two nuclear division occurs but only one occur in mitosis.

(ii)  Refer to blog content

3.    (SSCE, 1998 Q3) Outline the main events during meiotic division in organisms (Diagrams are not required)

(b) How can meiosis bring about variation in organisms?

Solution

Prophase I

1. The chromosomes condense and membrane disintegrate

2.  The homologous chromosomes pair up forming bivalents.

3.  Pairing of homologous chromosomes may cross-over at points called chiasmata.  Crossing over result in exchange of fragments. 

Metaphase I

1.  The bivalents line up along the cell equator and attach to spindle fibres at the centromeres.

Anaphase I

1.  The homologous chromosomes separate and move towards the opposite pole of the cell.

Telophase I

1.  The nuclear membrane reappears and the spindle fibres disappear.

2. The process of cytokinesis occurs, forming two haploid daughter cells.

Prophase II

1.  The nucleoli and the nuclear envelope disappear,

2. The centrioles move toward the poles.

Metaphase II

1. The spindle fibres grow from the centrioles and attach to the centromeres

2. The sister chromatids line up along the cell equator

Anaphase II

1. The sister chromosomes move towards the opposing poles.

Telophase II

1. Chromatids reach the opposite poles of the cells.

2. The nuclear membrane and nucleolus reappears.

3. Cleavage or cell wall forms which eventually produces a total of four daughter cells, each cell having haploid set of chromosomes. 

(c) The separation of each pair of alleles of homologous chromosomes during meiosis in the process of gamete formation, and the subsequent recombination during fertilization is a random that brings alleles from parents together in different combination. Secondary, due to crossing over that occurs during meiosis, new combinations of genes are formed in the gametes which can as well lead to variation.

4.      (SSCE, 1999 Q2) (a) Explain each of the following terms

(b) chromosome number   

(ii) chiasmata  

(iii) telophase        

(iv) reduction division

(v) chromosomal replication

(b) State the significance of each of the terms listed in (a) above

Solution

(i) Chromosome number: is the total number of chromosomes in a somatic cell. It is fixed for any particular species. Man has 46, tobacco plant has 48

(ii) Chiasmata: point at which non-sister chromatids of homologous chromosomes cross-over or meet and exchange genetic material.

(iii) Telophase: is one of the phases in cell division where chromosomes reach the poles, nucleolus reappear and nuclear membrane form around them.

(iv) Reduction division (meiosis): is type cell division which produced daughter cells that have half the chromosome number of the parent

(v) Chromosomal replication: this is the duplication of chromosome during interpose, so that single chromatid at the end of telophase reappear in the following prophase as pairs of chromatids. 

Significance

(i) Chromosome number: It helps in sex determination of an organism e.g., in bees the drones are diploid and worker are haploid. It determines the characteristics of an individual species. Change in chromosome number give rise to new species.

(ii) Chiasmata: this keeps homologous pairs together as well as evolution potential due to genetic recombination.

(iii) Telophase: new nucleus is reconstituted which results in gamete formation in meiosis and formation of somatic cells.

(iv) Reduction division (meiosis): allows formation of gametes, brings about variation and evolutionary potential and fixing of parental genotypes.

(v) Chromosomal replication: prevents continual reduction of genetic material at each cell division.


5.      (SSCE, 2005 Q7) (a) In which organ does meiosis occur in

(i) Mammals         

(ii) Flowering plants

(b) Compare mitosis with meiosis in a tubular form.

(c) What is the importance of meiosis and mitosis in living organism?

Solution

(a) (i) Mammals: testis and ovary

(ii) Flowering plants: anther and ovary

(b) & (c)  Refer to blog content