4.Spore Formation (sporulation)
Spores are very minute unicellular asexual reproductive bodies which get dispersed and form new individuals on germination.They occur in bacteria,fungi,algae and many protists
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| Sporulation |
5.Fragmentation
In this method of reproduction,the parent body divides into many pieces called fragments,each of which develops into a new offspring by regeneration.This method is quite common in algae , fungi and bryophytes. It is also common in some sponges ,platyhelminthes , nemertines and echinodermates.
Itvis caused by mechanical disturbance , or wave action (e.g.,sponges) death and decay of older part etc. It is a common method of reproduction in green filamentous alga like Spirogyra. Here all the cells are capable for photosynthesis , growth and division. Therefore each filaments grows into new filament.
6.Regeneration
The capacity of the animal by which lost or cut out orgamns are repaired , replaced or restored or even whole body is reconstituted from a small fragment of it during post-embryonic life of the organism is known as regeneration. The lost organs are replaced by growth or remodelling of somatic cells.
The process of regeneration was discovered in Hydra in 1740 by Trembly. It is helpful in multiplication of some animals like Planaria and Hydra. Planaria has extremely high regenerative ability. The body of Planaria divides into many pieces , each piece has the ability to form a complete body.
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