Question

What type of pollination takes place in Vallisneria?
A. Pollination occurs in submerged conditions by water.
B. Flowers emerge above the surface of the water, and pollination occurs by insects.
C. Flowers emerge above the water surface, and pollen is carried by the wind.
D. Male flowers are carried by water currents to female flowers at the surface of the water.

Answer 1

Hint:
The process of transfer of pollen grains from the male reproductive part of the flower (anther) to the female reproductive part of the flower which is called stigma is said to be pollination. There are two types: cross-pollination, in which pollen grains from one flower's stigma touch another bloom's stigma, and self-pollination, in which pollen grains from an anther settle on the receptive stigma of the same flower.. There are different methods by which cross-pollination occurs such as Anemophily, Zoophily, anthropophilic etc.

Complete step by step answer:
Vallisneria is a freshwater aquatic plant. With the help of a long stalk, the female flower reaches the surface of the water while the male mature flowers release pollen grains on the water's surface. These pollen grains are carried to the stigma of the female flowers passively by water currents. Such a type of cross-pollination that occurs water surface is called epihydrophily (a type of hydrophily).
Zostera is a marine aquatic plant. The male gametes (pollen grains) are discharged into the water as the blooms of Zostera are entirely immersed, resulting in submerged water conditions for pollination.
The flowers of water lilies and water hyacinths are situated above the water surface and anthers do not release the pollen grains into the water; instead, they are transferred from one plant to another with the help of insects and pests or by the wind.
Thus, the correct answer is:- Male flowers are carried by water currents to female flowers at the surface of the water.

Option ‘D’ is correct

Note:
The pollen grains of the plants that adopt hydrophily (pollination by water) have a mucilaginous layer which protects them from getting wet.