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Class 12th Biology 2015 Set1 Delhi Board Paper Solution

Question 11

Double fertilization is reported in plants of both, castor and groundnut. However, the mature seeds of groundnut are non-albuminous and castor are albuminous. Explain the post fertilization events that are responsible for it.

Answer

Though double fertilisation is reported in both groundnut and castor, their mature seeds are different with respect to endosperm. The post-fertilisation events of them are as follows:



The primary endosperm nucleus repeatedly divides to give rise to free nuclei. This stage of development is called free nuclear endosperm.

Cell wall formation occurs next, resulting in a cellular endosperm.

At this stage, the endosperm may either be fully consumed by the growing embryo (non-albuminous seeds) as in the case of groundnut or be retained in the mature seed as in the case of castor and be used later in seed germination (albuminous seeds).