Capsella is used as a model for Dicot Embryo development and helps to show the dynamic relationship between the Embryo and the Endosperm.
A relatively large liquid Endosperm develops following double fertilization. It becomes cellular and is eventually metabolized by the Embryo such that there is very little Endosperm in the mature Seed.
The Mature Capsella Seed is illustrated below.
The Seed consists of a
Seed Coat (Testa)
Endosperm
Embryo
The Embryo consists of
Root Apical Meristem (RAM)
Hypocotyl
Shoot Apical Meristem (SAM)
Two Cotyledons (Dicot)