Embryo studies fall into two categories, firstly the comparative and devel-opmental studies and secondly those aimed at embryo culture (or haploid, embryo sac culture).
Embryology and the sequence of cell divisions involved in embryo sac formation and following fertilization have become very specialized fields of study. There is a large body of comparative data available to the student, most of which is applied to evolutionary and taxonomic studies.
Embryo culture involves dissecting out embryos and growing them in culture media. This is sometimes done to ensure development and estab-lishment of particular individual plants, but more often as a means of vege-tative propagation.