In case of plants, the mitosis is involved in which of the following?
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Microgametogenesis
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Megagametogenesis
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Root and shoot growth
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All of the above
Which of the following is the shortest stage of cell cycle?
Meiotic division of one cell gives rise to how many haploid cells?
During 1882, the term mitosis was first used by which of the following?
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Sutton
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Flemming
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Strausberger
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Boveri
Which of the following is the longest stage of cell cycle?
In which organism, meiosis take place shortly after the formation of zygotes?
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Many fungi
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Chlamydomonas
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Yeast
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All of the above
Which of the following events occurs during metaphase of meiosis I ?
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Chiasma terminalization
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Arrangement of bivalents at equatorial plate
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Crossing over
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Separation of homologous chromosomes
Crossing over involves which of the following events ? DNA cleavage(=breakage) Ligation(=reunion) DNA degradation DNA synthesis
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I,II
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I,II,III,IV
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I,II,III
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I,II,IV
Synaptonemal complex is formed in which of the following substages of meiosis I ?
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Zygotene
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Pachytene
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Leptotene
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Diplotene
The period from one cell division to the next is called, which of the following?
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Cell cycle
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Cell period
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Cell generation
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Grand period
Cyclins were discovered by which of the following?
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Draetta and coworkers
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Watson and coworkers
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Weiner and coworkers
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Evans and coworkers
Which of the following best describes M phase kinase?
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A kinase
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A protein kinase
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A cyclin- dependent kinase
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A cyclin- dependent protein kinase
In which of the following, mitosis tales place?
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Pollen mother cell
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Pollen
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Both (b) and (c)
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Megaspore
Meiosis leads to the production of which of the following?
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Haploid cells (usually, gametes)
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New combinations of genes
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Lots of genetic variation
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All of the above
During which of the following stages histones are synthesized?
In adults animals, mitosis is usually concerned with the production of which of the following?
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Outer skin cells
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Bloods cells
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Gut epithelium
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all of the above
In plants, mitosis is confined to meristematic tissues of which of the following?
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Root-tips and shoot-tips
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Young leaves and cambium
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Flower buds
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All of the above
Which of the following is not correct about mitotic cell division?
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It produces genetic variation.
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Mitosis leads to the production of two daughter cells from each parent cell.
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It is involved in the production of new organs like roots, shoots, and leaves in plants.
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It involves separation of sister chromatids only.
Consider the order of following terms related to different stages of mitotic cell division: Anaphase, interphase, prophase, metaphase, telophase. Select the correct order in cell cycle from the options listed below:
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(a) Interphase → metaphase → anaphase → telophase → prophase
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(b) Interphase → prophase → metaphase → telophase → anaphase
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(c) Interphase → prophase → metaphase → anaphase telophase
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(d) Prophase → metaphase → interphase → anaphase →telophase
The metaphase of mitotic cell division is characterized by which of the following ? 1. Disappearance of nuclear membrane and nucleolus. II. Arrangement of highly condensed chromosomes on the equatorial plate. III. Presence of spindle apparatus. IV. Absence of relational coiling between sister chromatids.
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I. II. IV
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I, II. III, IV
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II, III, IV
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I, II, III
Which of the following are the significant events of the first meiotic division ? 1. Pairing between homologous chromo-somes. II. Crossing over between non-sisterchromatids of homologous chromo- somes. III. Arrangement of bivalents on equatorial plate. IV. Separation of homologous chromosomes and their migration towards opposite poles.
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I, II, III, IV
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I, III, IV
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I, II, III
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II, III, IV
The most likely mechanism of crossing over involves which of the following?
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Two single-strand breaks
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One double-strand break
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Two double-strand breaks
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Copy-choice DNA replication
Which of following pairs depicts a doubtful relationship? (
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Synaptonemal complex and crossing (b) Pairing between homologous chromo-over.
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somes and regular distribution of chromosomes.
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Separation of homologous chromosomes and segregation of genes.
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One round of DNA synthesis followed by two nuclear divisions and reduction in chromosome number
Inactivation of M phase kinase, following the onset of M phase, begins with which of the following?
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(a) Phosphorylation
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(b) Cyclin destruction
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(c) Dephosphorylation
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(d) All of the above
A single cell in each ovule differentiates into which of the following?
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Microspore mother cell
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Megaspore
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Megaspore mother cell
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Adventitious embryo
The concentration of G₂ cyclins is the highest during which stage of mitosis?
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G₁ phase
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G₂ phase
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S phase
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M phase
M phase kinase activation involves the monitoring of which of the following?
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Completeness of DNA replication
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Absence of DNA damage.
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Increase in cell mass.
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All of the above.
Which is the correct option about crossing over? 1. Heteroduplex regions are produced. recombinant joints per recombi- II. Two nation event are formed. III. Formation of hybrid DNA always leads to recombination. IV. Gene conversion may occur due to crossing over.
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I, II, IV
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I, II, III
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II, III
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I, II, III, IV
Which of the following is monitored during cell cycle regulation?
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Completeness of DNA replication
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Doubling of cell size
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Absence of DNA damage
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All of the above
Which of the following cyclins is regulated by proteolytic destruction after M phase initiation?
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Cyclins D and E
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Cyclins A and B
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Cyclins B
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Cyclins A