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During ovulation only one ovum is produc...

During ovulation only one ovum is produced. But doing one ejaculation about 200,000,000 sperms are released. Write the significance of increase in the number of sperms.

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About 200 million (1 million = 10 lakhs) sperm are discharged by a single ejaculation. Since the sperms have to travel a great distance through the female genital tract there is the trouble with chemical haz ards and mechanical obstacles. Such a huge number of sperms is neces sary to ensure a few to reach the anterior part of the fallopian tube, the site of fertilisation. Of the sperm only one sperm succeeds in fertilization the ovum present there.
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The entry of only one sperm ensured into an ovum during fertilization in humans, Explain.

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NEW JOYTHI PUBLICATION-HUMAN REPRODUCTION -NEW EVALUATION
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  2. Copy the diagram. Identify and label any five parts.

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  3. During ovulation only one ovum is produced. But doing one ejaculation ...

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  4. Find out the correct sequence from below. a. Fertilisation to zygote...

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  5. The ovum is surrounded by four membranes. How can a sperm enter and fu...

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  6. Observe the diagrams and answer the questions that follow. a. Giv...

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  7. During cleavage of the mammalian zygote, the resultant blastomeres bec...

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  8. A human ovum is released on the 14th day of menstrual cycle. a. Wha...

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  9. A connection between foetal membrane and uterine wall is known as plac...

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  10. The germ layers are given. Complete the organs derived from the germ l...

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  11. A woman has conceived and implantation occurred within her uterus. Dis...

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  12. A fertilised egg is a blue print for future development. Justify the s...

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  13. Amnion is an effective shock absorber. Comment on it.

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  14. First trimester of pregnancy is critical. Give reason.

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  15. Find the odd one out in each group and justify. a.Vasa efferentia, e...

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  16. Observe the diagram. a. Where is this event taking place? b. Wr...

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  17. Change in nucleus, acrosome formation, changes in mitochondria, centri...

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  18. The relaxin secreted by placenta relaxes the pubic ligaments during pa...

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  19. Observe the flowchart showing the hormonal control of Menstrual cycle ...

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  20. The diagram of human blastocyst is given below . a.Identify A and...

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