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Corpus luteum in pregnancy has a long li...

Corpus luteum in pregnancy has a long life. However if fertilisation does not take place, it remains active only for 10-12 days. Explain.

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This is because of a neural signal given by the maternal endometrium to its hypothalamus in presence of a zygote to sustain the gonadotropin (LH) secretion, so as to maintain the corpus luteum as long as the embryo remains there. In the absence of a zygote , therefore the corpus luteum can not be maintained longer.
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TRUEMAN BIOLOGY-REPRODUCTION-SECTION-B
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  2. How many haploid cells are present in mature female gametophyte of a f...

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  3. Placenta acts as an endocrine tissue. Justify.

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  4. The number of taxa exhibiting asexual reproduction is drastically redu...

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  5. Draw the sketch of a zoospore and a conidium. Mention two dissimilarit...

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  6. Given below are the events that are observed in an artificial hybridiz...

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  7. Why does the zygote begin to divide only after the division of primary...

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

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

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  10. what is bursa of fabricius

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  11. In GIFT, gametes are transferred to the fallopian tube. Can gametes be...

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  12. Briefly explain IVF

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  13. All reproductive tract infections RTIs are STDs, but all STDs are not ...

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  14. What do you understand by amniocentesis ? Why is there a statutory ba...

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  15. When and where do chorionic villi appear in humans ? State their funct...

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  16. How does cleistogamy ensure autogamy?

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  17. Explain the steps that ensure cross pollination in an autogamous flowe...

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  18. Name all the haploid cells present in an unfertilized mature embryo-sa...

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  19. Differentiate between the two cells enclosed in a mature male gaemetop...

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  20. Explain the hormonal regulation of the process of spermatogenesis in h...

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