Free Cell Structure and Function MCQs with Answers

• A. Chromosomes will be fragmented
• B. Chromosomes will not segregate
• C. Recombination of chromosome arms will occur
• D. Chromosomes will not condense

Explanation: During anaphase in mitosis, sister chromatids segregate at opposite poles.

• A. A­(iii), B­(iv), C­(ii), D­(i)
• B. A­(i), B­(iv), C­(ii), D­(iii)
• C. A­(ii), B­(iv), C­(iii), D­(i)
• D. A­(iv), B­(iii), C­(ii), D­(i)

Explanation: Pachytene: Crossing­over takes place.Metaphase I: Chromosomes align at equatorial plate.Diakinesis: Terminalisation of chiasmata.Zygotene…

• A. Centromere of the chromosome
• B. Kinetosome of the chromosome
• C. Telomere of the chromosome
• D. Kinetochore of the chromosome

Explanation: Small disc-­shaped structures at the surface of the centromeres are called kinetochores.

• A. (i), (ii), (iii), (iv)
• B. (ii), (iii), (iv), (i)
• C. (ii), (i), (iv), (iii)
• D. (ii), (i), (iii), (iv)

Explanation: Prophase ­I of meiosis has been divided into five sub­stages which occur in the following sequence:Leptotene ➡ Zygotene ➡ Pachytene ➡…

• A. Twice the number of chromosomes and four times the amount of DNA
• B. Four times the number of chromosomes and twice the amount of DNA
• C. Twice the number of chromosomes and the amount of DNA
• D. Same number of chromosomes but twice the amount of DNA

Explanation: In diploid cells (somatic cells) during G 1 phase, DNA content is 2C and chromosome number is 2n whereas in haploid cells (gamete) during…

• A. G0 and G1
• B. G1 and S
• C. Only G2
• D. G2 and M

Explanation: The G2 phase holds the maximum 4C DNA content. The M phase (mitosis) also maintains the 4C DNA level throughout prophase, metaphase, and…

• A. Amount of DNA doubles in each cell
• B. Amount of DNA remains same in each cell
• C. Chromosome number is decrease
• D. Amount of DNA is reduced to half in each cell

Explanation: S phase (Synthesis Phase) is the phase of the cell cycle in which DNA is replicated, occurring between G1 phase and G2 phase.

• A. Pachytene
• B. Zygotene
• C. Diplotene
• D. Diakinesis

Explanation: (a) : Pachytene is characterized by the appearance of recombination nodules, the sites at which crossing over occurs between non­sister…

• A. Bivalent
• B. Axoneme
• C. Equatorial plate
• D. Kinetochore

Explanation: During the zygotene stage, chromosomes start pairing together and this process of association is called synapsis.

• A. Cytokinesis: Cell plate formed, mitochondria distributed between two daughter cells
• B. Telophase: Endoplasmic reticulum and nucleolus not reformed yet
• C. Telophase: Nuclear envelope reforms, Golgi complex reforms
• D. Late anaphase: Chromosomes move away from equatorial plate, Golgi complex not present

Explanation: The figure given in the question shows a stage of mitotic cell division called the telophase stage.

• A. Zygotene
• B. Pachytene
• C. Diplotene
• D. Leptotene

Explanation: During zygotene or zygonema of meiotic prophase I the chromosomes become shorter and thicker.

• A. Kinetochore
• B. The centromere and the kinetochore
• C. Centromere, kinetochore and the areas adjoining the centromere.
• D. Centromere

Explanation: In metaphase, chromosomes consisting of two sister chromatids get arranged at equator.

• A. Metaphase ­- Spindle fibers attached to kinetochores, centromeres split and chromatids separate
• B. Metaphase -­ Chromosomes moved to spindle equator, chromosomes made up of two sister chromatids
• C. Anaphase ­- Centromeres split and chromatids separate and start moving away
• D. Late prophase ­- Chromosomes move to spindle equator

Explanation: Each metaphase chromosome is a duplicated structure which consists of two sister chromatids, attached at a point called centromere or…

• A. Metaphase I
• B. Anaphase II
• C. Prophase I
• D. Prophase II

Explanation: (c) : During gamete formation, the enzyme recombinase participates during pachytene stage of prophase I.

• A. Prophase I during meiosis
• B. Prophase II during meiosis
• C. Prophase of mitosis
• D. Both prophase and metaphase of mitosis

Explanation: The given figure shows crossing over i.e., exchange of segments between two homologous chromosomes.

• A. Metaphase I
• B. Metaphase II
• C. Anaphase I
• D. Anaphase II

Explanation: During anaphase I, from each tetrad two chromatids of a chromosome move as a unit (dyad) to one pole of a spindle, and the remaining two…

• A. Chromatids separate but remain in the cen­tre of the cell in anaphase.
• B. Chromatids start moving towards opposite poles in telophase.
• C. Golgi complex and endoplasmic reticulum are still visible at the end of prophase.
• D. Chromosomes move to the spindle equator and get aligned along equatorial plate in metaphase.

Explanation: (d) : The plane of alignment of the chromosomes at metaphase is referred to as the metaphase plate.

• A. Satellites
• B. Secondary constrictions
• C. Kinetochores
• D. Centromeres

Explanation: The key feature of metaphase is the attachment of spindle fibres to kinetochores of chromosomes.

• A. Late prophase
• B. Early metaphase
• C. Late metaphase
• D. Early prophase

Explanation: During early prophase of mitosis, the nucleus and cell become spheroid. The viscosity and refractivity of cytoplasm increases.

• A. During G2 stage of prophase
• B. During S­-phase
• C. During the entire prophase
• D. During telophase

Explanation: During the S phase or synthetic phase, the replication of DNA takes place.