Description
The myriads of flowers that we enjoy gazing at, the scents and the perfumes that we swoon over, the rich colours that
attract us, are all there as an aid to sexual reproduction.
Flowers do not exist only for us to be used for our own selfishness. All flowering plants show sexual reproduction.
A look at the diversity of structures of the inflorescences, flowers and floral parts, shows an amazing range of
adaptations to ensure formation of the end products of sexual reproduction, the fruits and seeds. In this chapter, let us understand the morphology, structure and the processes of sexual reproduction in flowering plants (angiosperms).
Flowers are the seat of sexual reproduction in angiosperms. In the flower, androecium consisting of stamens represents the male reproductive
organs and gynoecium consisting of pistils represents the female reproductive organs.
A typical anther is bilobed, dithecous and tetrasporangiate. Pollen grains develop inside the microsporangia. Four wall layers, the epidermis, endothecium, middle layers and the tapetum surround the microsporangium. Cells of the sporogenous tissue lying in the centre of the microsporangium, undergo meiosis (microsporogenesis) to form tetrads of microspores. Individual microspores mature into pollen grains.
Course Content
Introduction
Structure of Flower
Male Sex Organ in Flower
Microsprogenesis
Pollen Grains
Female sex organ - Pistil
Pollination
Sexual reproduction in flowering plants
Agents of pollination
Megasporogenesis
Embryo sac formation
Double Fertilisation
Before and After Fertilisation
Embryogeny
Formation of Seed and Fruit
Some important terms
Pollen-Pistil Interaction
Endosperm Formation
More About Pollen Grains
Outbreeding Devices
Artificial Hybridisation
Embryogeny - Monocot vs Dicot
These are fantastic concepts that will lay a strong theoretical foundation for you and help you with competitive exams like NEET , CET, Foundation