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.