- In unisexual flowers, the male and female reproductive organs are separated, so the pollen from a male flower cannot directly pollinate the female flower of the same plant.
- As a result, Autogamy is not possible, since self-pollination is blocked by the separation of sexes.
- Geitonogamy is also prevented, as it requires pollen to be transferred between different flowers of the same plant.
- However, Xenogamy, which involves pollen transfer between different plants, is still possible because it doesn't depend on the same plant's male and female flowers.
The property of unisexuality of flowers prevents Geitonogamy, but does not prevent Xenogamy. Hence, the correct answer is option (C).
Many of the flowering plants producing hermaphrodite flowers have developed many devices to discourage self-pollination and to encourage cross-pollination. Given below is a picture of one such outbreeding device in a flowering plant. Study the picture and answer the questions that follow:
(a) Explain how the given type of pollination is advantageous to the plant.
(b) Can this flowering plant show geitonogamy? Justify your answer.
Match the pollination types in List-I with their correct mechanisms in List-II:
List-I (Pollination Type) | List-II (Mechanism) |
---|---|
A) Xenogamy | I) Genetically different type of pollen grains |
B) Ophiophily | II) Pollination by snakes |
C) Chasmogamous | III) Exposed anthers and stigmas |
D) Cleistogamous | IV) Flowers do not open |
Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): Both wind and water pollinated flowers are not very colorful and do not produce nectar.
Reason (R): The flowers produce enormous amounts of pollen grains in wind and water pollinated flowers.
In light of the above statements, choose the correct answer from the options given below:
Arrange the following states in sequence (highest to lowest) according to their reserves of iron ore and choose the correct option.
I. Jharkhand
II. Karnataka
III. Chhattisgarh
IV. Odisha