Question

Give reason why groundnut seeds are exalbuminous and castor seeds are albuminous?

Answer 1

A seed is the part of a plant which has the ability to grow into a brand new plant. It can also be referred to as a reproductive structure which has a short life span. There are three common parts; an embryo, nutrient supplement for the embryo and a seed coat. Also, endosperm is tissue that surrounds and nourishes the embryo in the seeds of angiosperms.

Complete answer:
The seeds in which food is stored mainly in the endosperm and retains it even at maturity are called albuminous seeds. And the seeds which lack endosperm and food is stored only in cotyledons are called exalbuminous seeds. It was found that groundnut seeds are exalbuminous because groundnuts do not have residual endosperm as it is completely consumed during embryo development, hence it is known as exalbuminous seed. Whereas, in castor seeds, endosperm is not completely used during embryonic development and it retains a part of endosperm at maturity, hence called albuminous seeds.

Note: The endosperm stores the food of the albuminous seeds that is present till maturity.
In dicotyledonous exalbuminous seeds, the kernel is the embryo.
Groundnut seeds are the seeds that ripen underground and are the major oil seed crop.
Castor seed provides castor oil which has many uses.
The ripe castor seeds can be pressed and outer covering can be removed to obtain castor oil. The outer covering is also called the hull.