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(a) Draw a diagrammatic sectional view o...

(a) Draw a diagrammatic sectional view of a mature anatropous ovule and label the following parts in it :
(i) that develops into seed coat.
(ii) that develops into an embryo after fertilization.
(iii) that develops into an endosperm in an albuminous seed.
(iv) through which the pollen tube gains entry into the embryo sac.
(v) that attaches the ovule to the placenta.

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(b) Characters of wind pollinated flowers - (i) Flowers are small usually unisexual. inconspicuous, colourless. odourless and nectarless. They are produced above the foliage (ii) In case of unisexual flowers, male flowers are more abundant. In bisexual flowers, stamens are produced in large number as compared to pistil. (iii) The anthers of wind pollinated flowers are extended and well-exposed so that the pollens are easily dispersed into wind currents. They have Large. often feathery stigma which may easily trap airborne pollen grains (iv) Pollen grains are small smooth dry and produced in large quantities. In some plants pollen are winged. (v) Non-essential parts are either absent or reduced (vi) The wind pollinated flowers often have a single ovule in each ovary and many flowers are packed into an inflorescence. Example is corn cob in which silky tassel is nothing but the stigma and style of many female flowers hanging in air to trap pollen grains
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(a) Draw a diagrammatic sectional view of the female reproductive system of human and label the parts (i) where the secondary oocytes develop (ii) which helps in collection of ovum after ovulation (iii) where fertilization occurs (iv) where implantation of embryo occurs.

Draw a longitudinal section of a flower and label the following parts : (i) Part that develops into a fruit (ii) Part that produces pollen grain (iii) Part that transfers male gametes (iv) Part that is sticky to trap

(a) Draw a diagram of a mature embryo sac of an angiosperm and label the following parts in it : (i) Filiform apparatus (ii) Synergids (iii) Central cell (iv) Egg cell (v) Polar nuclei (vi) Antipodals (b) Write the fate of egg cell and polar nuclei after fertilization.

(a) Draw a sectional view of human female reproductive system and label the part where (i) eggs develop. (ii) fertilization take place. (iii) fertilized egg gets implanted. (b) Describe, in brief, the changes the uterus undergoes (i) to receive the zygote. (ii) if zygote is not formed.

Study the following statements and select the correct option. (i) Tapetum nourishes the developing pollen grains. (ii) Hilum represents the junction between ovule and funicle. (iii) In aquatic plants such as water hyacinth and water lily, pollination is by water. (iv) The primary endosperm nucleus is triploid.

Which of the following statement(s) is/are true about self-incompatibility? (i) It is a device to prevent inbreeding. (ii) It provides a biochemical block to self-fertilization. (iii) It ensures cross-fertilization (iv) It is governed by pollen-pistil interaction. (v) It is governed by series of multiple alleles. (vi) It prevents self-pollen (from the same flower of other flowers of the same plant) from fertilizing the ovules by inhibiting pollen germination of pollen tube growth in the pistil.

Go through the following statements (i) HCG from placenta stimulates the sertoli cells of the male foetus to produce testosterone and is thus indirectly ivolved in the development of male external genitalia (ii) Sertoli cells secrete a protein called inhibin, which suppresses FSH synthesis. (iii) Humans have haemo-endothelial type of placenta. (iv) oxytcin stimulates the placenta to secrete prostaglandins which in turn stimulate more contractions of uterus. Which of these correct?

TRUEMAN BIOLOGY-REPRODUCTION-SECTION-D
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  2. Mention any two sexually transmitted diseases in human and its causiti...

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  3. Give reasons why: (i) Most zygotes in angiosperms divide only afte...

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  4. Describe in sequence the events that lead to the development of a 3-ce...

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  5. (a ) Trace the development ofmegaspore mother cell up to the formation...

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  6. (a ) Draw a labelled longisectional view of an albuminous 'seed'· (b...

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  7. Describe the post-zygotic events leading to implantation and placenta ...

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  8. Although sexual reproduction is a long drawn, energy-intensive complex...

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  9. Embryo sacs of some apomictic species appear normal but contain diploi...

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  10. Describe oestrous cycle. In which group of animals is it observed.

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  11. Give examples for physical and surgical contraceptive methods.

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  12. The following is the illustration of the sequence of ovarian events (a...

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  13. Mention the function of Synergids and polar nuclei in embryo sac.

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  14. Describe the structure of blastula.

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  15. Mention the fate of all the components of the embryo sac after fertili...

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  16. (a) Draw a diagrammatic sectional view of a mature anatropous ovule an...

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  17. (a) Draw a diagrammatic sectional view of the female reproductive syst...

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  18. Mention examples for: a. Insect pollinated flower. b. Wind pollina...

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  19. Mention two types of gametogenesis.

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  20. (a) Draw a diagram of a mature embryo sac of an angiosperm and label t...

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