2. REGENERATION
Regeneration is the sequence of morphogenetic
events that restores the normal structure of an organ
after its partial or total ampulation.
It is the process of renewal, restoration, and tissue
growth that makes genomes, cells, organisms,
and ecosystems resilient to natural fluctuations or
events that cause disturbance or damage.
Some examples : Hydra , Planaria
3. REGENERATION IN ANIMALS
1] HYDRA :
👉 It is a genus of freshwater polyp in the
phylum cnidaria with highly proliferative stem
cells that gives them the ability to regenerate
their entire body.
👉 Regeneration among hydra occurs as foot
regeneration arising from the basal part of the
body, and head regeneration, arising from the
apical region.
4. 2] PLANARIA
👉 Planaria can be cut into pieces, and each
piece can regenerate into a complete organism.
👉 Cells at the location of the wound site
proliferate to form a blastema that will
differentiate into new tissues and regenerate
the missing parts of the piece of the cut
planaria.
5. TYPES OF REGENERATION
There are two types of regeneration :
Epimorphosis or Epimorphic Regeneration
Morphallaxis or Morphollatic regeneration
6. 1] Epimorphosis or Epimorphic Regeneration
This type of regeneration involve the
reconstruction of the missing parts by local
proliferation from the blastema, or addition of
parts to remaining piece.
For example :
Regeneration of tail, limbs and lens in
Amphibians & Reptilia.
7. 2] Morphallaxis or Morphollatic regeneration :
This type of regeneration involving reorganization of
the remaining part of the body of an animal .
Morphallatic regeneration does not include the
formation of blastemal and there is no proliferation.
Instead the existing tissue undergoes re-arrangement
and it is transformed into the new organ.
For example : Cnidarian hydra
