Pearl formation shot note , in +3 zoology students

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PEARL FORMATION
             

         Their are 3 types of pearl formation named as,
              1. Natural             2. Cultured            3. Imitation
- Pearl is a hard glistening object produced within the shoft tissue of a living molluca.
- Pearl are found in different type of colour like that pink ,white, black ,gree, pink etc.



PEARL FORMATION
- The foreign object enters the body of a bivalve ( one type of mollusca) in between the shell and mantle.
- The mantle immediately gets irritated and encloses it like a sac.
- The mantle wall then starts secreting layers and around the foreign object.
- The mantle wall secretes continuously several layer around the foreign object, and finally pearl is formed.
- The foreign object like that sand particle,parasite,small larva or any object of organic and inorganic origin.
  ...................................................................................................

*      Prof.- Dr ramakant pradhan 
best of luck for your exam , you study and ask u doubt or other wise dout in other long question in biology ask me in comment box .ok  student by . 


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