Board Questions

Cell Division

Q. 1 Match the following

Column A Column B

Chromosomes become arranged in a horizontal plane at

the equator.

Anaphase

Daughter chromosomes move to opposite poles of the

spindle.

Prophase

Chromosomes become visible as fine, long threads. Telophase

Chromosomes lose their distinctiveness and gradually

become transformed into chromatin network.

Metaphase

Ans.

Column A Column B

Chromosomes become arranged in a horizontal plane at

the equator.

Metaphase

Daughter chromosomes move to opposite poles of the

spindle.

Anaphase

Chromosomes become visible as fine, long threads. Prophase

Chromosomes lose their distinctiveness and gradually

become transformed into chromatin network.

Telophase

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Q.2 Choose the correct answer from the following:

Duplicate chromosomes are joined at a point termed:

(a) Centrosome (b) Centromere

(c) Centriole (d) Chromatid

Ans. Centromere

Q.3 Given below is a certain functional activity of specific structures in the body of

living organisms. Name the structure responsible for the same.

It initiates cell division in animal cells.

Ans. Centrosome.

Q.4 Given aside is a diagram, representing a stage during mitotic cell division in an

animal cell.

(i) Identify the above stage. Give a reason to support

your answer.

Ans. Prophase: Nuclear membrane disappears.

(ii) Name the cell organelle that forms the ‘aster’.

Ans. Centrosome.

(iii) Name the parts labeled 1, 2 and 3.

Ans. 1. Centromere

2. Chromosome

3. Spindle fibers

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(iv) Name the stage that follows this stage of Mitosis. How can this stage be

indentified?

Ans. Metaphase: Chromosome line up on metaphase plate.

(v) Mention two points of difference between ‘mitosis’ and ‘meiosis’ with regard

to:

1. The number of daughter cells formed.

2. The chromosome number in the daughter cells.

Ans.

Mitosis Meiosis

Two daughter cells are formed. Four daughter cells are formed.

Same no of chromosomes as that of

parent.

Half the number of chromosomes that of

parent cell.

Q.5 Cytokinesis is division of cytoplasm. State True or False.

Ans. True

Q.6 Rewrite the terms in the correct order so as to be in logical sequence.

Metaphase, Telophase, Prophase, Anaphase.

Ans. Prophase, Metaphase, Anaphase, Telophase.

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Q.7 Match the following

Column A Column B

Meiosis Cell

Protoplasm

Sperm

Ans. Meiosis – sperm

Q.8 Differentiate between the following on the basis of what is given in the

brackets:

(i) Karyokinesis and Cytokinesis (Explain the term)

(ii) Mitosis and Meiosis (Number of daughter cells formed)

Karyokinesis Cytokinesis

It is the division of nucleus It is the division of cytoplasm

Mitosis Meiosis

It forms two daughter cells. It forms four daughter cells.

Q.9 The diagram given alongside represents a stage during mitotic cell division in

an animal cell:

(i) Indentify the stage. Given a reason to support

your answer.

Ans. Anaphase

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Reason: Spindle fibers contract, the centromere divides and the two sister

chromatids of each chromosomes separates and move towards opposite poles.

(ii) Name the parts labeled 1,2 and 3.

Ans. 1. Centromere

2. Spindle fibres

3. Sister chromatid

(iii) What is the Chromosome number of the cell?

Ans. Four pairs.

(iv) Draw a neat, labeled diagram as it would appear in the next stage. Name the

stage.

Ans. Stage – Telophase

Q.10. Name the membrane that disappears during late prophase.

Ans. Nuclear membrane

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Q.11. Arrange in sequentical order, without changing the first term.

Interphase, Anapahse, Prophase, Telophase,Metaphase

Ans. Interphase Prophase Metaphase Anaphase Telophase

Q.12. State whether the following statement are true or false, if false change the

last word.

Duplicated chromosomes remain attached at a point termed centrosome- True

Q.13. Draw a diagram of the nucleus of a cell, Having chromosome number 6, as it

would appear in the metaphase of mitosis and label the following parts.

Aster, Spindle, Chromatid and Centrososme.

Q.14. Mention difference between mitosis and meiosis’ on the basis of number of

daughters formed and chromosome number of daughter cell.

Mitosis Meiosis

Produces two daughter cells Produces four daughter cell

It has diploid (2n) number of

chromosomes

It has haploid (n) number of

chromosomes

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Q.15. State whether the following statement are true or false, if false change the

last word or first word

The resting stage in mitosis is called interphase. = True

Q.16. Give specific function of centrosome.

Ans. Initiates and regulates cell division

Q.17. Identify and name the process.

Chromosomes appears thread- like.

Ans. Telophase or Interphase

Q.18. Study the diagram and answer the question that follows:

(i) Identify the cell division

Ans.Anaphase

(ii) Label the parts A,B,C and D

Ans. A- Spindle fibres

B-Cell wall

C- Chromatid

D- Centrosomere

(iii) What is the unique feature observed in this stage.

Ans. Two chromatid and unbroken centromere starts moving towards the opposite

poles of the cells.

(iv) Where does this type of cell division usually occur.

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Ans. Somatic cell

(v) How many daughter cells are formed from this type of cell divsion

Ans. Two daughter cells

(vi) Identify the type of cell? Give reason to your answer.

Ans. Plant cell. Because it has cell wall

Q.19. Name the following:

The type of cell division which occurs in the cells of the reproductive organs.

Ans. Meiosis

Q.20. State whether the following statements are true or false, if false change the

last word or first word only.

(i) Mitosis is the type of cell division occurring in the cells of injured part of the

body.

Ans. True

(ii) Chromosomes other than the pair of sex chromosome are called alleles.

Ans. False. Chromosomes other than the pair of sex chromosomes are called

autosomes.

Q.21 Given below is a diagram of a double structure of DNA

(i) Name the four nitrogenous bases that form a DNA

molecule.

Ans. Adenine, Thymine, Guanine and cytosine.

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(ii) Give the full form of DNA.

Ans. Deoxy Ribonucleic Acid.

(iii) Name the unit of heredity.

Ans. Gene

(iv) Mention two points of difference between Mitosis and Meiosis.

Mitosis Meiosis

It takes place in body cells or somatic

cells.

It takes place in reproductive organ to

form gametes.

The process is completed in one

sequence, to from two cells.

The process is completed in two

successive divisions to form four

haploid cells.

Q.22 Given below is a diagram representing a stage during mitotic cell division in

an animal cell:

(i) Identify the above stage. Given a reason to

support your answer.

Ans. Prophase. The nucleolus and nuclear

membrane disappear.

(ii) Name the parts labeled 1, 2, 3, and 4.

Ans. 1. Aster, 2. Chromosomes, 3. Centromere,

4. Spindle fiber.

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(iii) What is the function of part 3?

Ans. It is a small region which attach the sister chromatid.

(iv) Name the stage that comes just after the stage shown in the diagram. Draw a

well labelled diagram of this stage.

Ans. Stage after prophase is metaphase

Q.23 What is the full form of RNA?

Ans. Ribonucleic Acid.

Q.24 . State whether the following statements are true or false, if false change the

last word or first word only:

(i) Lysosomes is a part of cell in which chromosomes are present.

Ans. False, Nucleus is a part of cell in which chromosomes are present.

(ii) Centromere is the organelle of the cell that initiates cell division.

Ans. False, Centrosome is the organelle of the cell that initiates cell division.

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Q.25 Study the diagram and answer the question that follows:

(i) Name the parts labelled 1, 2 and 3.

Ans. 1. Aster 2. Spindle fibers 3. Chromatids.

(ii) Identify the above stage and give a reason to

support your answer.

Ans. Late Anaphase

(iii) Mention where in the body this type of cell

division occurs.

Ans. In division of somatic and germ cells.

(iv) Name the stage prior to this stage and draw a diagram to represent the same.

Ans. Metaphase.

Q.26 Give the exact location of the centrosome.

Ans. A region surrounding the centrioles, located near nucleus in the cytoplasm.

Q.27 Arrange in logical sequence:

Karyakinesis, S- phase, Cytokinesis, G1- phase, G2- phase (cell cycle)

Ans. G1- phase, S- phase, G2- phase (cell cycle), Karyakinesis, Cytokinesis.

Q.28 Draw a well labelled diagram to show the metaphase stage of Mitosis in an

animal cell having four chromosomes.

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Q.29 Give biological reason. Gametes have a haploid number of chromosomes.

Ans. Gametes (egg or sperm) are haploid, because it is forms by meiotic division.

It is denoted by ‘n’.

A set of unpaired chromosomes is said to be haploid.

It is essential because when the male and female gametes fuse during fertilization

they from a zygote which is diploid (2n), that is, normal number of chromosomes.

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