CBSE Class 10 Science 2022 · Paper 31/4/2 · Question 5

Regeneration is the ability of a fully differentiated organism to give rise to new individual organisms from its body parts: if the organism is cut or broken into pieces, many of the pieces grow into separate, complete individuals. Regeneration in Planaria: when a Planaria is cut into a few pieces, each piece can grow into a complete worm. Regeneration is carried out by specialised cells, which proliferate and make a large number of cells. From this mass of cells, different cells undergo changes to become the various cell types and tissues of the missing parts. These changes take place in an organised sequence called development, so each piece becomes a complete Planaria.