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During reproduction the chromosome nmber...

During reproduction the chromosome nmber (2n) reduces to half (n) in the gametes and again the original number (2n) is restored in the offspring. What are the processes through which these events take place?

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The meictic cell division reducers the chromosome numbers to half during gametogenesis and diploid (2n) number of chromosome is restored by the union of male and female gamete through processs of fertilisation.
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NCERT EXEMPLAR-HUMAN REPRODUCTION -Human Reproduction
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  2. The mother germ cells are transformed into a mature follicle through s...

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  3. During reproduction the chromosome nmber (2n) reduces to half (n) in t...

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  4. What is the difference between a primary oocyte and a secondary oocyt...

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  5. What is the significance of ampullary-isthmic junction in the female r...

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  6. How does zona pellucida of ovum help in preventing polyspermy?

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  7. Mention the importance of LH surge during menstrual cycle.

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  8. Which type of cell division forms spermatids from the secondary sperma...

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  9. A human female experiences two major changes menrache and menopause du...

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  10. (a) How many spermatozoa are formed from one secondary spermatocyte? ...

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  11. Corpus luteum in pregnancy has a long life. However if fertilisation d...

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  12. What is foetal ejection reflex? Explain how it leads to parturition?

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  13. Except endocrine function, what are the other functions of placenta.

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  14. Why doctors recommend breast feeding during initial period of infant g...

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  15. What are the events that take place in the ovary and uterus during fol...

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  16. Given below is a flow chart showing ovarian changes during menstrual c...

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  17. Given a schematic labelled diagram to represent oogenesis (without des...

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  18. What are the changes in the oogonia during the transition of a primary...

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  19. What role does pituitary gonadotropins play during follicular and ovul...

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  20. Meiotic division during oogenesis is different from that in spermatoge...

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