Class 11 Biology - Chapter Cell cycle and Cell Division NCERT Solutions | What is the significance of meiosis?
What is the significance of meiosis?
Meiosis is the process involving the reduction in the amount of genetic material. It comprises two successive nuclear and cell divisions, with a single cycle of DNA replication. As a result, at the end of meiosis II, four haploid cells are formed.
Significance of meiosis
1. Meiosis maintains the chromosome number from generation to generation. It reduces the chromosome number to half so that the process of fertilisation restores the original number in the zygote.
2. Variations are caused by the cross-over and the random distribution of homologous chromosomes between daughter cells. Variations play an important role in evolution.
3. Chromosomal mutations are brought about by the introduction of certain abnormalities. These chromosomal mutations may be advantageous for an individual.
More Questions From Class 11 Biology - Chapter Cell cycle and Cell Division
- Q:- Describe the following:
(a) synapsis
(b) bivalent
(c) chiasmata
Draw a diagram to illustrate your answer. - Q:- How does cytokinesis in plant cells differ from that in animal cells?
- Q:- Describe the events taking place during interphase.
- Q:- Why is mitosis called equational division?
- Q:- What is G0 (quiescent phase) of cell cycle?
- Q:- Can there be DNA replication without cell division?
- 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:
(i) Chromosomes are moved to spindle equator
(ii) Centromere splits and chromatids separate
(iii) Pairing between homologous chromosomes takes place
(iv) Crossing over between homologous chromosomes takes place - Q:- 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 - Q:- Find examples where the four daughter cells from meiosis are equal in size and where they are found unequal in size.
Popular Questions of Class 11 Biology
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- Q:-
Which of the following is not correct?
(a) Robert Brown discovered the cell.
(b) Schleiden and Schwann formulated the cell theory.
(c) Virchow explained that cells are formed from pre-existing cells.
(d) A unicellular organism carries out its life activities within a single cell. - Q:- What are macromolecules? Give examples.
- Q:- What are the factors affecting the rate of diffusion?
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2 Comment(s) on this Question
Thanks for the answers,it's really helpful
Nice Answer
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