(a) Draw a shematic labelled diagram of a fertilised embryo sac of an angiosperm.
(b) Describe the stages in embryo development in a dicot plant .

Explanation

(a)
(b) Embryo develops at the micropylar end of the embryo sac where the zygote is situated . Must zygotes divide only after certain amount of endosperm is formed . This adaptation provides assured nutrition to the developing embryo . The later stages of embryo development ( embryogeny ) are similar in monocotyledons and dicotyledons .
In dicotyledonous embryo the zygots given rise rise to the preembryo and subsequently to the globular heart shaped and mature embryo. In the dicot seed the embryo consists of an embryonal axis two cotyledons plumule radicle or root tip . The root tip is covered with root cap.