The male parts are called stamens and usually surround the pistil. The stamen is made up of two parts: the anther and filament.

pistil

Stamen Terms

The stigma is located in the gynoecium of the flower. Its main function is to attract the pollen grains from the air with its sticky tip for reproduction to take place.

Stamen: The pollen producing part of a flower, usually with a slender filament supporting the anther. Anther: The part of the stamen where pollen is produced. Pistil: The ovule producing part of a flower.

The two major types of stamen cycly are uniseriate, having a single whorl of stamens, and biseriate, with two whorls of stamens. If additional whorls are present, the terms triseriate, tetraseriate, etc., can be used.

Parts of a flower

The stamens are male reproductive structures that produce pollen. The carpels are female reproductive structures that produce egg cells and protect a developing baby plant, or embryo.

Carpels are the female reproductive organs of flowering plants (angiosperms), enclose the ovules, and develop into fruits. The presence of carpels unites angiosperms, and they are suggested to be the most important autapomorphy of the angiosperms, e.g., they prevent inbreeding and allow efficient seed dispersal.

Carpels are the basic units of the gynoecium and may be free (distinct) or fused (connate). The term pistil is used in a similar manner to carpel – in some situations the terms are equivalent in meaning but not in others. For example, a flower represented by G 1 has a single carpel or a single pistil.

Pollination takes two forms: self-pollination and cross-pollination. Self-pollination occurs when the pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant.

2) Now, the pollination in Vallisneria is epihydrophily. This type of pollination occurs on the water surface. The female flower has a long pedicel that reaches to the surface of water and the male flower after it gets a break-down float on the water surface and releases pollen grain in the water.

Epihydrophily can be seen in plants that are grown above the surface of water whereas the hypohydrophily can be seen in submerged plants. The example of epihydrophily is Vallisneria whereas the example of hypohydrophily is the Ceratophyllum.

Vallisneria spiralis is an example of hydrophily. Female flowers reach the water’s surface temporarily to ensure pollination.

Ans. Xenogamy is transfer of pollen grains from anther of one flower to stigma of another flower of a different plant, while geitonogamy is transfer of pollen grains from anther of one flower to stigma of another flower on same plant. Ans.In Vallisneria,the male flowers are released on the water surface.