Class 12th Biology 2014 Set3 Delhi Board Paper Solution
Question 18
List the post-fertilisation events in angiosperms.
Answer
The various post-fertilisation events occurring in angiosperms are:
(i) Endosperm is formed before the development of embryo, as it provides nourishment to the developing embryo.
(ii) Zygote at the micropylar end undergoes successive divisions to form pro-embryo. It is followed by the formation of globular, heart-shaped and mature embryo.
(iii) A mature dicotyledonous embryo consists of two cotyledons, epicotyl and hypocotyl. On the other hand, a mature monocotyledonous embryo possesses only one cotyledon, a coleoptile and coleorrhiza.
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