CBSE Class 9 Answered

Fertilisation is the fusion of gametes to produce a new organism. In animals, the process involves a sperm fusing with an ovum, which eventually leads to the development of an embryo. Depending on the animal species, the process can occur within the body of the female in internal fertilisation, or outside in the case of external fertilisation. Double fertilization is seen in flowering plants.

Fertilization restores the diploid condition, since it involves the fusion of haploid gametes.