Free NEET Biology multiple-choice questions on Cell Division. Attempt each question and reveal the answer with a full explanation.
Who among the following first explained that cells divided and new cells are formed from pre-existing cells (Omnis cellula-e cellula)? Rudolf Virchow Theodore Schwann Matthias Schleiden Aristotle Spindle fibres attach on to :- Telomere of the chromosome Kinetochore of the chromosome Centromere of the chromosome Kinetosome of the chromosome A metacentric chromosome is characterized by: A centromere in the middle, forming two equal arms A centromere slightly away from the middle, forming one short and one long arm A centromere close to the end, forming one very short and one very long arm A terminal centromere The stage of mitosis characterized by the disappearance of the nucleolus, Golgi complex, and endoplasmic reticulum is: Prophase Metaphase Anaphase Telophase Which of the following describes the 'Metaphase Plate'? The plane of alignment of chromosomes at the center of the cell The structure that pulls sister chromatids apart The region where the cell membrane invaginates during cytokinesis The protein disc at the centromere Under ideal laboratory conditions, a typical bacterial cell like E. coli can divide approximately every: 20 minutes 60 minutes 90 minutes 24 hours Chromatids of a homologous chromosome pair which are not from the same chromosome are called: Non-sister chromatids Sister chromatids Homologous segments Recombinant chromatids The site of attachment of spindle fibers to the chromosomes is the: Kinetochore Centromere Telomere Secondary constriction Rudolf Virchow modified the cell theory by stating 'Omnis cellula-e cellula'. In which year did he propose this addition? 1855 1838 1839 1860 The term 'Chromatin' was coined by which scientist to describe the thread-like structures in the nucleus that stain with basic dyes? Flemming Robert Brown Strasburger Camilo Golgi Which of the following scientists was the first to see and describe a live cell? Antonie van Leeuwenhoek Robert Hooke Matthias Schleiden Theodore Schwann What is the primary significance of mitosis in multicellular organisms? Cell repair and replacement of lost cells Introduction of genetic variability Reduction of chromosome number by half Production of gametes In meiosis crossing over is initiated at : Pachytene Leptotene Zygotene Diplotene In the process of DNA replication, the leading strand is synthesized while the lagging strand is synthesized . Continuously; Discontinuously Discontinuously; Continuously 3' to 5'; 5' to 3' In the nucleus; In the cytoplasm Semi-conservative replication of DNA was first demonstrated in eukaryotes using radioactive thymidine in chromosomes of Vicia faba by: Taylor and colleagues Meselson and Stahl Hershey and Chase Watson and Crick The stage of Meiosis I characterized by the terminalization of chiasmata is: Diakinesis Diplotene Pachytene Zygotene Which of the following mutations results in the change of every amino acid in a polypeptide chain from the point of mutation onwards? Frameshift mutation Point mutation Nonsense mutation Silent mutation During DNA replication, Okazaki fragments are used to elongate: The lagging strand away from the replication fork The leading strand towards the replication fork The lagging strand towards the replication fork The leading strand away from the replication fork Given below is a schematic break-up of the phases / stages of cell cycle : Which one of the following is the correct indication of the stage / phase in the cell cycle ? A-Cytokinesis B-Metaphase C-Karyokinesis D-Synthetic phase A stage in cell division is shown in the figure. Select the answer which gives correct identification of the stage with its characteristics. Telophase – Nuclear envelope reforms, golgi complex reforms. Late Anaphase – Chromosomes move away from equatorial plate, golgi complex not present. Cytokinesis – Cell plate formed, mitochondria distributed between two daughter cells. Telophase – Endoplasmic reticulum and nucleolus not reformed yet. The enzyme recombinase is required at which stage of meiosis : Pachytene Zygotene Diplotene Diakinesis A cell at telophase stage is observed by a student in a plant brought from the field. He tells his teacher that this cell is not like other cells at telophase stage. There is no formation of cell plate and thus the cell is containing more number of chromosomes as compared to other dividing cells. This would result in :- Aneuploidy Polyploidy Somaclonal variation Polyteny The stage during which separation of the paired homologous chromosomes begins is Diakinesis Diplotene Pachytene Zygotene Which of the following is not a characteristic feature during mitosis in somatic cells ? (1) Spindle fibres (2) Disappearance of nucleolus (3) Chromosome movement (4) Synapsis Match the following with respect to meiosis array ll (a) Zygotene & (i) Terminalization (b) Pachytene & (ii) Chiasmata (c) Diplotene & (iii) Crossing over (d) Diakinesis & (iv) Synapsis array Select the correct option from the following (iv) (iii) (ii) (i) (i) (ii) (iv) (iii) (ii) (iv) (iii) (i) (iii) (iv) (i) (ii) Which stage of meiotic prophase shows terminalisation of chiasmata as its distinctive feature? Zygotene Diakinesis Pachytene Leptotene The process of appearance of recombination nodules occurs at which sub stage of prophase I in meiosis? Zygotene Pachytene Diplotene Diakinesis Match List I with List II : array ll List I & List II A. M Phase & I. Proteins are synthesized B. G 2 Phase & II. Inactive phase C. Quiescent stage & III. Interval between mitosis and initiation of DNA replication D. G 1 Phase & IV. Equational division array Choose the correct answer from the options given below : A-III, B-II, C-IV, D-I A-IV, B-II, C-I, D-III A-IV, B-I, C-II, D-III A-II, B-IV, C-I, D-III Select the correct statements. A. Tetrad formation is seen during Leptotene. B. During Anaphase, the centromeres split and chromatids separate. C. Terminalization takes place during Pachytene. D. Nucleolus, Golgi complex and ER are reformed during Telophase. E. Crossing over takes place between sister chromatids of homologous chromosome. Choose the correct answer from the options given below: A and C only B and D only A, C and E only B and E only Given below are two statements: Statement I : Chromosomes become gradually visible under light microscope during leptotene stage. Statement II : The beginning of diplotene stage is recognized by dissolution of synaptonemal complex. In the light of the above statements, choose the correct answer from the options given below: Both Statement I and Statement II are true Both Statement I and Statement II are false Statement I is true but Statement II is false Statement I is false but Statement II is true Match List I with List II : array llll ; & List I; (Sub Phases of Prophase I) & ; & List II; (Specific Characters) A. & Diakinesis & I. & Synaptonemal complex formation B. & Pachytene & II. & Completion of terminalisation of chiasmata C. & Zygotene & III. & Chromosomes look like thin threads D. & Leptotene & IV. & Appearance of recombination nodules array Choose the correct answer from the options given below A-IV, B-II, C-III, D-I A-I, B-II, C-IV, D-III A-II, B-IV, C-I, D-III A-IV, B-III, C-II, D-I Select the correct match: Polytene chromosomes - Oocytes of amphibians Submetacentric chromosomes - L-shaped chromosomes Allosomes - Sex chromosomes Lampbrush chromosomes - Salivary glands of insects Which of the following describes the 'Bouquet stage' during the cell cycle? The arrangement of chromosomes toward the centriole during Leptotene The alignment of chromosomes at the equator during Metaphase The pairing of homologous chromosomes during Zygotene The terminalization of chiasmata during Diakinesis During which stage of the cell cycle is the concentration of 'Cyclin-dependent kinases' ( CDKs ) relatively constant, but their activity fluctuates? Throughout the entire cell cycle Only during S phase Only during M phase Only during G 0 phase Which of the following statements is correct with respect to cell cycle? DNA content of cell remains constant during entire cell cycle A cell in G1 phase has double the amount of DNA than a cell in G2 phase Each chromosome has two chromatids in G1 phase Nerve cells in adult human are in G0 state The correct sequence of adult cell cycle phases is . G1-G2-S-M G1-M-G2-S G1-S-G2-M S-M-G2-G1 Given below are two statements : Statement I : Chromosomes are fully condensed at the end of prophase I. Statement II : Meiosis I resembles mitosis. In the light of the above statements, choose the most appropriate answer from the options given below : Both Statement I and Statement II are true Both Statement I and Statement II are false Statement I is correct, but Statement II is false Statement I is incorrect, but Statement II is true At what phase of meiosis homologous chromosomes are separated ? (1) Anaphase II (2) Prophase I (3) Prophase II (4) Anaphase I The correct sequence of phases of cell cycle is (1) G 1 S G 2 M (2) M G 1 G 2 S (3) G 1 G 2 S M (4) S G 1 G 2 M Cells in G 0 phase : (1) terminate the cell cycle (2) exit the cell cycle (3) enter the cell cycle (4) suspend the cell cycle Some dividing cells exit the cell cycle and enter vegetative inactive stage. This is called quiescent stage ( G 0 ). This process occurs at the end of G 1 phase S phase G 2 phase M phase Identify the correct statement with regard to G 1 phase (Gap 1) of interphase. Reorganisation of all cell components takes place. Cell is metabolically active, grows but does not replicate its DNA. Nuclear Division takes place. DNA synthesis or replication takes place. Dissolution of the synaptonemal complex occurs during Zygotene Diplotene Leptotene Pachytene The stage of mitosis where chromosomes align at the equator is Metaphase Prophase Anaphase Telophase Which of the following stages of meiosis involves division of centromere? Metaphase II Anaphase II Telophase II Metaphase I Match List-I with List-II. array llll ; & List-I & ; & List-II (a) & S phase & (i) & Proteins are synthesized (b) & G 2 phase & (ii) & Inactive phase (c) & Quiescent stage & (iii) & Interval between mitosis and initiation of DNA replication (d) & G 1 phase & (iv) & DNA replication array Choose the correct answer from the options given below. a-iv, b-ii, c-iii, d-i a-iv, b-i, c-ii, d-iii a-ii, b-iv, c-iii, d-i a-iii, b-ii, c-i, d-iv The fruit fly has 8 chromosomes ( 2n ) in each cell. During interphase of Mitosis if the number of chromosomes at G 1 phase is 8, what would be the number of chromosomes after S phase? 16 4 32 8 The centriole undergoes duplication during: Prophase Metaphase G 2 phase S-phase The appearance of recombination nodules on homologous chromosomes during meiosis characterizes : Bivalent Sites at which crossing over occurs Terminalization Synaptonemal complex Which one of the following never occurs during mitotic cell division? Movement of centrioles towards opposite poles Pairing of homologous chromosomes Coiling and condensation of the chromatids Spindle fibres attach to kinetochores of chromosomes Select the incorrect statement with reference to mitosis: Spindle fibres attach to centromere of chromosomes Chromosomes decondense at telophase Splitting of centromere occurs at anaphase All the chromosomes lie at the equator at metaphase Regarding Meiosis, which of the statements is incorrect? DNA replication occurs in S phase of Meiosis-II Pairing of homologous chromosomes and recombination occurs in Meiosis-I Four haploid cells are formed at the end of Meiosis-II There are two stages in Meiosis, Meiosis-I and II Among eukaryotes, replication of DNA takes place in : M phase S phase G 1 phase G 2 phase Which of the following stages of meiosis involves division of centromere? Metaphase I Metaphase II Anaphase II Telophase If a cell has 24 chromosomes at the end of the G 1 phase, how many chromosomes will it have at the end of the S phase? 24 48 12 36 Given below are two statements: Statement I : During G₀ phase of cell cycle, the cell is metabolically inactive. Statement II : The centrosome undergoes duplication during S phase of interphase. In the light of the above statements, choose the most appropriate answer from the options given below: Both Statement I and Statement II are correct Both Statement I and Statement II are incorrect. Statement I is correct but Statement II is incorrect. Statement I is incorrect but Statement II is correct. Spindle fibers attach to kinetochores of chromosomes during Prophase Metaphase Anaphase Telophase Following are the stages of cell division : A. Gap 2 phase B. Cytokinesis C. Synthesis phase D. Karyokinesis E. Gap 1 phase Choose the correct sequence of stages from the options given below : C-E-D-A-B E-B-D-A-C B-D-E-A-C E-C-A-D-B What is the main function of the spindle fibers during mitosis? To regulate cell growth To separate the chromosomes To synthesize new DNA To repair damaged DNA Match List I with List II : array llll ; & List-I (Phase of cell cycle) & ; & List-II (Activity) A. & G 1 phase & I. & Actual cell division occurs B. & S phase & II. & Cell is metabolically active and continuously grows but does not replicate its DNA C. & G 2 Phase & III. & Synthesis of DNA occurs and the amount of DNA per cell doubles D. & M phase & IV. & Proteins are synthesized while cell growth continues array Choose the correct answer from the options given below : A-III, B-IV, C-I, D-II A-IV, B-I, C-II, D-III A-I, B-II, C-III, D-IV A-II, B-III, C-IV, D-I In which animal do haploid cells divide mitotically to produce gametes? Male honeybees Male grasshoppers Male earthworms Male frogs Which stage of meiosis involves the division of centromeres? Anaphase II Anaphase I Metaphase II Telophase I In the 9+2 arrangement of axoneme, '9' refers to Peripheral doublets of microtubules Central microtubules Radial spokes Central sheath A chromosome with the centromere situated close to its end, forming one extremely short and one very long arm, is called Acrocentric Metacentric Sub-metacentric Telocentric Cells in the G 0 phase of the cell cycle Suspend the cell cycle Exit the cell cycle Enter the cell cycle Terminate the cell cycle Which of the following is the correct order of events in the cell cycle? G 1 S G 2 M G 1 G 2 S M S G 1 G 2 M M G 1 G 2 S Centrioles duplicate in the cytoplasm during which phase of the cell cycle? S phase G 1 phase G 2 phase Prophase Which enzyme catalyzes the crossing over between non-sister chromatids of homologous chromosomes? Recombinase RNA polymerase DNA ligase Endonuclease In which stage of mitosis do chromosomes lose their individuality and collect in a mass at opposite poles? Telophase Anaphase Metaphase Prophase During which phase of the cell cycle are proteins for spindle fibers synthesized? G 2 phase G 1 phase S phase M phase Which of the following describes the '9 + 0' arrangement of microtubules? Centriole Cilia Flagella Basal body of prokaryotes The stage between two meiotic divisions is called Interkinesis Interphase Cytokinesis Quiescent stage The 'cartwheel' appearance is characteristic of which cellular structure? Centriole Nucleolus Chloroplast Mitochondria The quiescent stage ( G 0 ) of the cell cycle is a state where cells Are metabolically active but no longer proliferate unless called on to do so. Have terminated the cell cycle and are dead. Are rapidly replicating their DNA . Are preparing for the M phase. During which phase of the cell cycle is the synthesis of histone proteins most active? S phase G 1 phase G 2 phase M phase The final stage of meiotic prophase I, characterized by the terminalization of chiasmata, is: Diakinesis Diplotene Pachytene Zygotene Four healthy people in their twenties got involved in injuries resulting in damage and death of a few cell of the following. Which of the cells are least likely to be replaced by new cells - Osteocytes Liver cells Neurons Malpighian layer of the skin During Meiosis II, the main event that distinguishes it from Meiosis I is the: Separation of sister chromatids Separation of homologous chromosomes Crossing over Pairing of homologous chromosomes Which type of chromosome has a centromere slightly away from the middle, resulting in one shorter arm and one longer arm (L-shaped during anaphase)? Sub-metacentric Metacentric Acrocentric Telocentric During Meiosis I, the process by which homologous chromosomes separate while sister chromatids remain attached at their centromeres is called: Disjunction Non-disjunction Synapsis Cytokinesis In the axoneme of eukaryotic cilia and flagella, how many radial spokes are present? 9 2 11 18 During the S phase of the cell cycle, besides DNA replication, which of the following events occurs in the cytoplasm of animal cells? Duplication of centrioles Synthesis of lysosomes Breakdown of nuclear envelope Spindle fiber attachment During Meiosis I, the stage characterized by the appearance of recombination nodules, the sites at which crossing over occurs, is: Pachytene Zygotene Diplotene Diakinesis The '9 + 0' arrangement of microtubules is seen in the: Centriole Cilia Flagella Axoneme The formation of a syncytium, a multinucleate condition, occurs when: Karyokinesis is not followed by cytokinesis Cytokinesis occurs without karyokinesis The cell enters G 0 phase Meiosis II is skipped The 'Basal Body' from which cilia and flagella emerge is structurally similar to: Centrioles Ribosomes Nucleosomes Mitochondria In some vertebrate oocytes, which stage of Meiosis I can last for months or even years? Diplotene Pachytene Zygotene Leptotene At what stage of the cell cycle are histone proteins synthesized in a eukaryotic cell - During telophase During S-phase During G-2 stage of prophase During entire prophase In the liquid endosperm of coconut, the multinucleate condition formed by the failure of cytokinesis after karyokinesis is called: Syncytium Coenocyte Mesokaryon Plasmodium During the early stages of Prophase in animal cells, two star-like structures called develop from the centrosomes. Asters Spindle fibers Kinetochores Centrioles Which of the following events does NOT occur during the G 2 phase of the cell cycle? DNA replication Synthesis of tubulin protein Growth of the cell Synthesis of RNA During Prophase I of meiosis, the 'bouquet stage' occurs in which sub-stage? Leptotene Zygotene Pachytene Diplotene The amount of DNA per cell is halved during: Meiosis I and Meiosis II S phase Mitosis only Meiosis I only What happens to the DNA content and chromosome number of a cell after it completes the S phase of the cell cycle? DNA content doubles, but chromosome number remains the same. Both DNA content and chromosome number double. DNA content remains the same, but chromosome number doubles. Both DNA content and chromosome number remain the same. During which phase of the cell cycle is the synthesis of tubulin proteins, required for the formation of spindle fibers, most prominent? G 2 phase G 1 phase S phase M phase During meiosis, the process of 'Terminalization' occurs in which stage of Prophase I? Diakinesis Diplotene Pachytene Zygotene Identify the incorrect statement regarding Meiosis I. Sister chromatids separate during Anaphase I. Homologous chromosomes pair during Zygotene. Crossing over occurs between non-sister chromatids in Pachytene. The nuclear membrane disappears during Diakinesis. The 'Recombination nodule' is formed during which sub-stage of Prophase I? Pachytene Zygotene Leptotene Diplotene The complex formed by a pair of synapsed homologous chromosomes is called Equatorial plate Kinetochore Bivalent Axoneme Which of the following statements about the 'Quiescent stage' ( G 0 ) of the cell cycle is correct? Cells in G 0 phase are metabolically active but no longer proliferate unless called upon to do so. Cells in G 0 phase are metabolically inactive. Cells in G 0 phase have double the DNA content of G 1 phase. Cells in G 0 phase are permanently stuck and cannot re-enter the cell cycle. The movement of chromosomes towards the poles during anaphase is characterized by: Centromeres leading the way with arms trailing behind. Chromatid arms leading the way with centromeres trailing behind. The entire chromosome moving sideways towards the poles. Chromosomes remaining at the equator while spindle fibers contract. During which phase of the cell cycle does the human cell spend approximately 95 % of its duration? Interphase Prophase Metaphase Anaphase In the cell cycle, the 'spindle assembly checkpoint' occurs during which stage to ensure all chromosomes are properly attached to spindle fibers? Metaphase Prophase Anaphase Telophase The centrosome is an organelle usually containing two cylindrical structures called centrioles. These centrioles are surrounded by: Amorphous pericentriolar materials A double membrane A thick cell wall Cisternae Which phase of the cell cycle is typically the most variable in duration among different cell types in a multicellular organism? G 1 phase S phase G 2 phase M phase During which phase(s) of the cell cycle is the amount of DNA in a cell at 4C level if the initial amount is denoted as 2C ? Only G 2 G 2 and M G 0 and G 1 Only S What will be the DNA content of a cell at G 1 phase if the DNA content after meiosis I is 20 pg ? 40 pg 20 pg 80 pg 10 pg Crossing over takes place between which chromatids and in which stage of the cell cycle? Non-sister chromatids of homologous chromosomes at Pachytene Sister chromatids of homologous chromosomes at Zygotene Non-sister chromatids of non-homologous chromosomes at Pachytene Sister chromatids of non-homologous chromosomes at Zygotene Small, disc-shaped structures at the surface of the centromeres to which spindle fibers attach are called Kinetochores Chromomeres Centrioles Telomeres During which phase(s) of cell cycle, amount of DNA in a cell remains at 4C level if the initial amount is denoted as 2C ? G0 and G1 G1 and S Only G2 G2 and M The stage of meiosis I where the synaptonemal complex dissolves and chiasmata become visible is Diplotene Pachytene Zygotene Diakinesis Match the following: (a) Zygotene - (i) Chiasmata visibility, (b) Pachytene - (ii) Synapsis, (c) Diplotene - (iii) Crossing over, (d) Diakinesis - (iv) Terminalization. a-ii, b-iii, c-i, d-iv a-iii, b-ii, c-i, d-iv a-i, b-ii, c-iii, d-iv a-iv, b-iii, c-ii, d-i During meiosis I, at which stage do the homologous chromosomes separate while sister chromatids remain associated at their centromeres? Anaphase I Anaphase II Metaphase I Metaphase II A chemical used to inhibit mitosis by preventing the formation of spindle fibers is Colchicine Actinomycin D Cyanide Methotrexate If a cell has 2n = 12 chromosomes in G 1 phase, what will be the number of chromosomes and the amount of DNA (relative to C ) after S phase? 12 chromosomes, 4C 24 chromosomes, 4C 12 chromosomes, 2C 24 chromosomes, 2C The basal body of both cilia and flagella is formed from a structure similar to: Centriole Microfilament Microtubule Nucleolus The major checkpoint of the cell cycle, where the cell 'decides' whether to enter the S phase or not, is located at: G 1 to S transition G 2 to M transition Metaphase to Anaphase transition Late S phase The secondary constriction on some chromosomes that gives rise to a 'satellite' is also known as the: Nucleolar Organizer Region (NOR) Kinetochore Centromere Telomere A bivalent consists of how many chromatids and centromeres? 4 chromatids and 2 centromeres 2 chromatids and 2 centromeres 4 chromatids and 4 centromeres 2 chromatids and 1 centromere If the DNA content of a diploid cell in G 1 phase is 2C , what will be the amount of DNA and the number of chromosomes respectively after S phase? 4C and 2n 4C and 4n 2C and 2n 2C and 4n In 'S' phase of the cell cycle :- Amount of DNA doubles in each cell. Amount of DNA remains same in each cell. Chromosome number is increased. Amount of DNA is reduced to half in each cell. In the cell cycle, the 'M-phase' checkpoint specifically ensures that: All chromosomes are properly attached to spindle fibers DNA replication is complete The cell has reached a sufficient size The environment is favorable for division During which phase of the cell cycle is the Maturation Promoting Factor ( MPF ) activated to trigger the start of mitosis? End of G 2 phase End of S phase End of G 1 phase End of Anaphase During Meiosis II, the two daughter cells undergo a division that resembles mitosis. What is the key difference between the start of Meiosis II and the start of Mitosis? Meiosis II is not preceded by S phase (DNA replication). Meiosis II involves the pairing of homologous chromosomes. Meiosis II results in diploid cells. Meiosis II has a much longer Prophase than Mitosis. A chromosome in which the centromere is located at the very tip, resulting in only one visible arm, is called: Telocentric Acrocentric Sub-metacentric Metacentric The formation of the synaptonemal complex occurs during which specific stage of Prophase I? Zygotene Leptotene Pachytene Diplotene Chiasmata are the visible expression of: Crossing over Synapsis Terminalization Segregation In 1838, which German botanist examined a large number of plants and observed that all plants are composed of different kinds of cells which form the tissues of the plant? Matthias Schleiden Theodore Schwann Rudolf Virchow Robert Brown What is the typical duration of the cell cycle for a human cell and a yeast cell respectively? 24 hours and 90 minutes 24 hours and 24 hours 90 minutes and 24 hours 1 hour and 90 minutes During which phase of mitosis does the nuclear envelope reform, and the nucleolus, Golgi complex, and ER reappear? Telophase Anaphase Metaphase Prophase In which stage of Prophase I does the nucleolus disappear and the nuclear envelope completely break down? Diakinesis Diplotene Pachytene Zygotene