ICSE Class 10

General instructions: Answer all questions. Marks are shown in brackets [ ].

Objective

1. 1.
   Which term describes the division of the nucleus?

   1. A. Karyokinesis
   2. B. Cytokinesis
   3. C. Mitosis
   4. D. Meiosis
   [1]
2. 2.
   The cell component visible only during cell division

   1. A. Mitochondria
   2. B. Chloroplast
   3. C. Chromosome
   4. D. Chromatin
   [1]
3. 3.
   Cytoplasm.

   1. A. Inside the cell between the nucleolus and the centromere
   2. B. Inside the cell between the nucleus and the cell membrane
   3. C. Inside the cell between the mitochondria and the cell membrane.
   4. D. Inside the cell near to the cell membrane
   [1]
4. 4.
   ________ is not a stage of mitosis.

   1. A. prophase
   2. B. Interphase
   3. C. Metaphase
   4. D. Anaphase
   [1]
5. 5.
   The process by which gametes are formed is called:

   1. A. Gametogenesis (Meiosis)
   2. B. Mitosis
   3. C. Fertilization
   4. D. Binary fission
   [1]
6. 6.
   The diagram shows a cell of an organism. The nucleus contains 12 chromosomes. After it divides by mitosis, how many chromosomes would be present in one of the daughter cells?

   1. A. 6
   2. B. 12
   3. C. 18
   4. D. 24
   [1]
7. 7.
   Condensation of chromosomes with centromere formation occurs in which phase of interphase?

   1. A. S-phase
   2. B. G₁-phase
   3. C. G₂-phase
   4. D. Prophase
   [1]
8. 8.
   In the following diagram of a section of a DNA molecule, what is the part labelled Q?

   1. A. Adenine
   2. B. Cytosine
   3. C. Thymine
   4. D. Uracil
   [1]
9. 9.
   A complex consisting of DNA strand and a core of histones is

   1. A. Nucleotide
   2. B. Nucleosome
   3. C. Centrosome
   4. D. Chromosome
   [1]
10. 10.
    The exchange of chromatid parts between the maternal and the paternal chromatids of a pair of a homologous chromosomes during meiosis is ________

    1. A. Crossing over
    2. B. Karyokinesis
    3. C. Meiosis
    4. D. Cytokinesis
    [1]
11. 11.
    Select the correct statement about $G_1$ phase:

    1. A. Cell is metabolically inactive.
    2. B. DNA in the cell does not replicate.
    3. C. It is not a phase of synthesis of macromolecules.
    4. D. Cell stops growing.
    [1]
12. 12.
    Which of the following correctly describes the relationship between cytokinesis and karyokinesis?

    1. A. Karyokinesis divides the nucleus; cytokinesis divides the cytoplasm afterward.
    2. B. Cytokinesis divides the nucleus; karyokinesis divides the cytoplasm afterward.
    3. C. Both processes occur simultaneously and divide the nucleus.
    4. D. Karyokinesis occurs only in plant cells; cytokinesis occurs only in animal cells.
    [1]
13. 13.
    During which stage of cell division do chromosomes arrange at the equator?

    1. A. Metaphase
    2. B. Prophase
    3. C. Anaphase
    4. D. Telophase
    [1]
14. 14.
    Which statement describes human cells formed by meiosis?

    1. A. They are genetically identical and they become gametes.
    2. B. They are genetically identical and they become tissues.
    3. C. They are not genetically identical and they become gametes.
    4. D. They are not genetically identical and they become tissues.
    [1]
15. 15.
    Which of the following correctly distinguishes between karyokinesis and cytokinesis?

    1. A. Karyokinesis divides the cytoplasm; cytokinesis divides the nucleus.
    2. B. Karyokinesis is the division of the nucleus; cytokinesis is the division of the cytoplasm.
    3. C. Karyokinesis occurs only in plant cells; cytokinesis occurs only in animal cells.
    4. D. Karyokinesis involves DNA replication; cytokinesis involves chromosome condensation.
    [1]
16. 16.
    At which point do duplicated chromosomes remain attached after DNA replication?

    1. A. Centromere
    2. B. Centrosome
    3. C. Telomere
    4. D. Kinetochore
    [1]
17. 17.
    The diagram given below represents a certain phenomenon which occurs during meiosis. Identify the labelled phenomenon using the terms — homologous chromosomes, chromatids, and crossing-over.

    1. A. Segregation of homologous chromosomes during anaphase I
    2. B. Exchange of segments between non-sister chromatids of homologous chromosomes, called crossing-over
    3. C. Random alignment of chromatids at the metaphase plate
    4. D. Separation of sister chromatids during anaphase II
    [1]
18. 18.
    Describe the role of mitochondria and chloroplasts during cell division. Which of the following statements best explains their behavior?

    1. A. They dissolve and are reassembled in daughter cells using nuclear DNA.
    2. B. They divide independently by simple fission and are distributed to daughter cells, guided by nuclear genes.
    3. C. They replicate only during interphase and are passively inherited by daughter cells.
    4. D. They fuse into a single structure before dividing equally between daughter cells.
    [1]
19. 19.
    The pairing of chromosomes during zygotene is known as:

    1. A. Synapsis
    2. B. Crossing over
    3. C. Disjunction
    4. D. Chiasma formation
    [1]
20. 20.
    How many mitotic divisions of a meristematic cell in a root tip are needed to produce 256 daughter cells?

    1. A. 8
    2. B. 16
    3. C. 32
    4. D. 64
    [1]