Which cell in the pollen grain is responsible for giving rise to the two male gametes?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Generative cell
Explanation: In the remaining species, the generative cell divides mitotically to give rise to the two male gametes.
Which of the following plants has an ovary containing a single ovule?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Wheat
Explanation: The number of ovules in an ovary may be one (wheat, paddy, mango) to many (papaya, water melon, orchids).
Identify the incorrectly matched pair regarding ovule structure.
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Micropyle: Basal part of the ovule
Explanation: Opposite the micropylar end is the chalaza, representing the basal part of the ovule. The micropyle is the small opening at the tip.
The Megaspore Mother Cell (MMC) differentiates in the:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Micropylar region of the nucellus
Explanation: Ovules generally differentiate a single megaspore mother cell (MMC) in the micropylar region of the nucellus.
What is the ploidy of the functional megaspore and the female gametophyte respectively?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: n and n
Explanation: The functional megaspore is haploid (n) formed by meiosis. It develops into the female gametophyte (embryo sac), which is also haploid (n).
The egg apparatus consists of:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: One egg and two synergids
Explanation: The egg apparatus, in turn, consists of two synergids and one egg cell.
In which type of pollination is the pollen genetically different from the stigma it lands on?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Xenogamy
Explanation: Xenogamy is the only type of pollination which during pollination brings genetically different types of pollen grains to the stigma.
Which characteristic is NOT associated with insect-pollinated flowers?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: D
Answer: Dry and light pollen
Explanation: Insect-pollinated flowers are large, colorful, fragrant and rich in nectar. Dry and light pollen is characteristic of wind pollination.
Which of the following is an example of a marine seagrass pollinated by water?
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: C
Answer: Zostera
Explanation: Some examples of water pollinated plants are Vallisneria and Hydrilla which grow in fresh water and several marine sea-grasses such as Zostera.
Pollen robbers are defined as:
[Sexual-Reproduction-in-Flowering-Plants] [class-xii]
Correct Option: B
Answer: Animals that consume pollen or nectar without bringing about pollination.
Explanation: Many insects may consume pollen or the nectar without bringing about pollination. Such floral visitors are referred to as pollen/nectar robbers.