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A mature, embryo-sac in a flowering plan...

A mature, embryo-sac in a flowering plant may possess 7-cells, but 8-nuclei. Explain with the help of a diagram only.

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In an embryo-sac, three cells are grouped together at the micropylar end and constitute the egg apparatus. The egg apparatus end and constitute the egg apparatus. The egg apparatus is consist of two synergids and one egg cell. The synergids have cellular thickenings at the micropylar tip called filiform apparatus, which plyas an important role in guiding the pollen tubes into the synergids. Three cells are at the chalazal end and are called antipodals. Thus, a typical angiosperm embryo-sac at maturity, though 8-nucleate is 7 celled.
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XII BOARD PREVIOUS YEAR PAPER ENGLISH-XII BOARDS-SECTION-B
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  2. (a) How does cleistogamy ensure autogamy? (b) State one advantage an...

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  3. A mature, embryo-sac in a flowering plant may possess 7-cells, but 8-n...

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  4. Describe the structure of a nucleosome.

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