Reproduction in Plants - Revision Notes

 CBSE Class 7 Science

Revision Notes 
Chapter – 12
Reproduction  in Plants

  •  All organisms multiply or reproduce offspring of their own kind.
  • In plants there are two modes of reproduction, namely (a) Asexual and (b) Sexual.
  • There are several methods of asexual reproduction such as fragmentation, budding, spore formation and vegetative propagation.
  • Sexual reproduction involves the fusion of male and female gametes.
  • In vegetative propagation new plants are produced from different vegetative parts such as leaves, stems and roots.
  • Flower is the reproductive part of a plant.
  • A flower may be unisexual with either the male or the female reproductive parts.
  • A bisexual flower has both the male and the female reproductive parts.
  • The male gametes are found inside the pollen grains and female gametes are found in the ovule.
  • Pollination is the process of transfer of pollen grains from the anther of one flower to the stigma of the same or another flower.
  • Pollination is of two types, self-pollination and cross-pollination. In self-pollination, pollen grains are transferred from the anther to the stigma of the same flower. In cross-pollination, pollen grains are transferred from the anther of one flower to the stigma of another flower of the same kind.
  • Pollination takes place in plants with the help of wind, water and insects.
  • The fusion of male and female gametes is called fertilization.
  • Fertilized egg is called zygote. Zygote develops into an embryo.
  • Fruit is the mature ovary whereas ovule develops into a seed, which contains the developing embryo.
  • Seed dispersal is aided by wind, water and animals.
  • Seed dispersal helps the plants to
    (i) prevent overcrowding,
    (ii) avoid competition for sunlight, water and minerals
    (iii) invade new habitats.