Flowers pollinated by flies and beetles secrete:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Foul odours
Explanation: The flowers pollinated by flies and beetles secrete foul odours to attract these animals.
The condition where male and female flowers are present on the same plant is called:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Monoecious
Explanation: If both male and female flowers are present on the same plant such as castor and maize, it is monoecious.
Monoecious plants (like Castor/Maize) prevent:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: A
Answer: Autogamy but not geitonogamy
Explanation: If both male and female flowers are present on the same plant (monoecious), it prevents autogamy but not geitonogamy.
Pollen-pistil interaction involves recognition of pollen mediated by:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Chemical components
Explanation: This dialogue is mediated by chemical components of the pollen interacting with those of the pistil.
During artificial hybridization in bisexual flowers, emasculation is done:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Before anther dehiscence
Explanation: Removal of anthers from the flower bud before the anther dehisces... is necessary.
In triple fusion, the second male gamete fuses with:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Polar nuclei
Explanation: The other male gamete moves towards the two polar nuclei located in the central cell and fuses with them.
The Primary Endosperm Cell (PEC) develops into:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Endosperm
Explanation: The central cell after triple fusion becomes the primary endosperm cell (PEC) and develops into the endosperm.
Endosperm development precedes embryo development to:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Provide assured nutrition
Explanation: Most zygotes divide only after certain amount of endosperm is formed. This is an adaptation to provide assured nutrition to the developing embryo.
Which part of the embryonal axis is located above the level of cotyledons?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Epicotyl
Explanation: The portion of embryonal axis above the level of cotyledons is the epicotyl.
The cylindrical portion below the level of cotyledons that terminates in the radicle is:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Hypocotyl
Explanation: The cylindrical portion below the level of cotyledons is hypocotyl that terminates at its lower end in the radicle.