Developmental Biology

Notes

Plant (Vegetative) Reproduction

The reproduction in which new individuals are formed from a single parent without the involvement of gametes and their fusion is called asexual reproduction. Vegetative propagation is the type of reproduction in which new plants are produced directly from any vegetative part of the parent plant. The part of the plant which produces new plant is called propagule. Vegetative propagation is of various types

Plant Gametogenesis

The process of reproduction in which two parents are involved to produce new generation by the fusion of meiotically formed male and female gametes is called sexual reproduction. In higher plants, sexual reproduction takes two steps: Sporogenesis : It is the process of formation of spores. Gametogenesis: It is the process of formation of gametes.

Pollination

The process of transfer of pollen grains from the anther to the stigma of the flower is called pollination. Pollination occurs at the two-celled stage of pollen grains. Pollination is of two types- Self-pollination and cross-pollination.

Fertilization And Embryogenesis

The process of fusion of male and female gametes to form the zygote is called fertilization. In angiosperms, the male gametes are carried to the egg cell by pollen tube, this phenomenon is called siphonogamy.The process of formation of an embryo from a zygote is known as embryogenesis. It can be studied under two headings: Dicot embryogenesis and Monocot embryogenesis