When the endosperms is completely eaten up by the growing embryo such type of seed is called non-endospermic seed.
Example - Pea , Gram , Bean , Groundnut etc
In non- endospermic seed the food is stored in the cotyledons .
The nucellus is generally used up by the developing embryo but in same seeds it persists in the form of a thin layer around the endosperm .
This residual nucellus is known as peri sperm .
Example- Castor , Black pepper , water lily etc
The outer integument from the outer hard dovering of seed i.e. the testa where as the inner integument forms the inner then coating of seed called as tegmen .
A scar left on one side of the seed is called as hilum .
It is the point of attachment of the funicle to the seed .
The micropyle of the integument remain as a small pore and function as an opening of the seed for the entry of water and oxygen during germination .
The final step of development of seed is the significant decrease in its water content which causes reduction in metabolic activities and lead to seed dormancy .
Seed germination is promoted by Gibberellin in hibited by ABA
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