Pollination

Introduction The pollination involves the transfer of pollen from male part of a plant, called stamen to the female part of the plant, known as carpel. This enables fertilization and sexual reproduction to occur. Pollen grains are contained within the pollen while the carpel contains the female gamete. In gymnosperms the pollen is directly applied to the ovule. The receptive part of the carpel is called a stigma in the flowers of angiosperms while the receptive part of the gymnosperm ovule is called the micropyle. Pollination is essential in the reproduction of flowering plants to produce offspring that shows genetic variation. Pollination involves wide field of studies such as botany, horticulture, entomology, and ecology. In 18th century, the pollination process as an interaction between flower and vector was first addressed by Christian Konrad Sprengel. It is important in horticulture and agriculture because fertilization as the end result of pollination is the key factor to fruiting.

Male and Female Gamates in Plants
What is a Pollen? Pollen is a substance produced by the anthers of seed-bearing plants that consists of numerous fine pollen grains containing male gametes. This means that pollen carries the cells which enable fertilization of plants so that plants may reproduce. The pollen wall protects the sperm nucleus while the pollen grain is moving from the anther to the stigma, it protects the vital genetic material from drying out and solar radiation. The pollen grain surface is covered with waxes and proteins. When pollen lands on a compatible pistil of flowering plants, it germinates and produces a pollen tube that transfers the sperm to the ovule of a receptive ovary. The outer pollen wall is composed of two layers, namely tectum and the foot layer. The tectum and foot layer are separated by the columella which is composed of strengthening rods. Pollen itself is not the male gamete, but