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[A] : Synergids play an important role i...

[A] : Synergids play an important role in directing the pollen tube growth .
[R] : Because synergids secrete some chemotropically active substance .

A

If both A and R are true and R is the correct explanation of A

B

If both A and R are true but R is not the correct explanation of A

C

If A is true and R is false

D

If both A and R are false

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TRUEMAN BIOLOGY-Plant Morphology & Reproduction -ASSERTION AND REASON
  1. Assertion. The time involved between pollination and fertilization var...

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  2. [A] : The presence of endothelium around the embryo sac and its cytolo...

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  3. [A] : Synergids play an important role in directing the pollen tube gr...

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  4. Assertion. In apomixis , plants of new genetic sequence are produced. ...

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  5. [A] : Nucleus of pollen grain divides meiotically and form a pollen tu...

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  6. [A]: Incompatibility is a gene physiological process. [R]: Moderate...

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  7. [A]: The pollen sterility has been attributed to the malfunctioning of...

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  8. [A]: The three cells of the egg apparatus are arranged in a triangular...

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  9. [A]: Pollen grains from male parent are mostly transferred to the stig...

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  10. [A]: The two sperms cells in a pollen tube often change their shape. ...

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  11. [A] : Synandrous condition is found in curcurbits. [R] : The male fl...

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  12. [A]: In certain plants the stem that twins around the support is hard ...

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  13. [A]: Leaf in Daucus carota is decompound. [R]: Saprophytic and paras...

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  14. [A]: The colour of flowers in Bougainvillia is due to the coloured bra...

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  15. [A]: The endosperm contains the triploid number of chromosomes. [R]:...

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  16. [A]: Spore mother cells within the anther pollen sacs form four haploi...

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  17. [A]: One diploid embryo sac mother cell develops within the nucellus o...

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  18. [A]: Triple fusion results in veg~tative fertiliza- tion of angiosperm...

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  19. [A]: Pollination is essential for fertilization. [R]: Abscission or...

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  20. [A]: The biennial plants live for two years. [R]: They flower in bo...

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