Class 11 Biology - Chapter Cell cycle and Cell Division NCERT Solutions | Analyse the events during every stage of
Analyse the events during every stage of cell cycle and notice how the following two parameters change
(i) Number of chromosomes (N) per cell
(ii) Amount of DNA content (C) per cell
During meiosis, the number of chromosomes and the amount of DNA in a cell change.
(i) Number of chromosomes (N) per cell
During anaphase I of the meiotic cycle, the homologous chromosomes separate and start moving toward their respective poles. As a result, the bivalents get divided into two sister chromatids and receive half the chromosomes present in the parent cell. Therefore, the number of chromosomes reduces in anaphase I.
(ii) Amount of DNA content (C) per cell
During anaphase II of the meiotic cycle, the chromatids separate as a result of the splitting of the centromere. It is the centromere that holds together the sister chromatids of each chromosome. As a result, the chromatids move toward their respective poles. Therefore, at each pole, a haploid number of chromosomes and a haploid amount of DNA are present. During mitosis, the number of chromosomes remains the same. The DNA duplicated in the S phase gets separated in the two daughter cells during anaphase. As a result, the DNA content (C) of the two newly-formed daughter cells remains the same.
More Questions From Class 11 Biology - Chapter Cell cycle and Cell Division
- Q:- Describe the following:
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(c) chiasmata
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- Q:- Distinguish anaphase of mitosis from anaphase I of meiosis.
- Q:- Name the stage of cell cycle at which one of the following events occur:
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(ii) Centromere splits and chromatids separate
(iii) Pairing between homologous chromosomes takes place
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- Q:- Can there be mitosis without DNA replication in S phase?
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1 Comment(s) on this Question
If you are talking about anaphase I and II then it should be meiosis and not mitosis
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