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(a) Draw a diagrammatic sketch of the se...

(a) Draw a diagrammatic sketch of the sectional view ofa typical anatropous ovule.
(b) List the components of the embryo sac and mention their fate on fertilisation.

Text Solution

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(a)
b) Components of embryo sac-After positive pollen pistil interaction, the pollen tube develops and enters the ovule through synergids guided by flliform apparalus.
1. One of the male gamete fertillses the female gamete to form diploid zygote.
2. The other male gamete fuses with the secondary nucleus (Polar nuclei if they are already formed) to form a triploid primary endosperm nucleus (PEN) which forms endosperm.
3. The three antipodals at chalazal end and synergids at micropylar end start degenerating.
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(a) Draw a labelled diagram of the sectional view of a typical anatropous ovule. (b) Mention the fate of all the components of the embryo sac after fertilization

(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. (b) Describe the characteristic features of wind pollinated flowers.

Knowledge Check

  • A diagrammatic view of a typical anatropous ovule is given below in which of the following option all five parts are correctly identified

    A
    `{:("A","B","C","D","E"),("Funicle","Micropyle","Female gametophyte","Embryo sac","Chalaza"):}`
    B
    `{:("A","B","C","D","E"),("Placenta","Micropyle","Egg","Embryo sac","Chalaza"):}`
    C
    `{:("A","B","C","D","E"),("Raphe","Micropyle","Egg","Embryo sac","Chalaza"):}`
    D
    `{:("A","B","C","D","E"),("Funicle","Micropyle","Nucellus","Embryo sac","Chalaza"):}`

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