S-Space College of Medicine/School of Medicine (의과대학/대학원) Dept. of Medicine (의학과) The Seoul Journal of Medicine The Seoul Journal of Medicine Vol. 27 No.1 (1986)
A Human Embryo of Streeter Age Group XV
사람배아(Streeter 연령군 XV)의 1예
- Chi, Je G.; Chee, Hyun K.
- Issue Date
- Seoul J Med, Vol.27 No.1, pp. 39-46
- A human embryo was sectioned serially and studied microscopically in order to
determine its proper age group based on the developmental status of the internal organs in
terms of selected definable characteristics. The embryo obtained incidentally from an hysterectomy
specimen had an ovulation age of 33 days and a crown-rump length of 7.4 mm.
Discernible morphological features of the embryo included closure of the lens vesicle,
separation of the otocyst from skin ectoderm and endolymphatic duct, a cervical sinus, a
narrow atrio-ventricular canal with an incompletely formed interventicular septum, bronchi in
the primary stage, and dorsal and ventral pancreatic buds.
The above observations strongly suggested that this embryo should be classed in the age
group XV of Streeter's developmental horizon.