Development of the embryo

A globular shape 0-7 days


At higher magnification, and one day later, the embryo starts to show a characteristic shape but shows no discernable cell patterning as yet. In contrast the cellular endosperm is hugely increased. It will support the embryo for the next ten days. ls at 3 days after fertilization.
The embryo at 5 days after flowering. Just a few cell divisions have produced an embryo with a characteristic globular shape and the beginnings of an internal structure. The two cell layers of the inner integument are still clearly seen. The other cell layers surrounding the embryo sac undergo complex changes.
The embryo is just 2 days old and may have divided only once. At this stage it is supported by the cellular endosperm, one of the products of divisions of the triploid fusion nucleus, which is close by at the base of the embryo sac.
The 7 day old embryo. In a few days further cell divisions have produced a central core of cells with a surrounding dermatogen layer. The scutellum will differentiate at the rounded end; the root pole has started to differentiate at the more pointed end. The embryo is cushioned by the nucellus and continues to be supported by the cellular endosperm.