2011 Lab 10 - Late Embryo
| 2011 Lab 10: Introduction | Early Embryo | Late Embryo | Fetal | Postnatal | Abnormalities | Online Assessment |
Week 8
Selected Head Images: B4 - Choroid Plexus | B5 - Cochlea | B6 - Cochlea
Palate
The dark "pear-shaped" central structure at the top is the developing tongue. The two pale regions either side are the palatal shelves, note that they have not yet fused in the midline (failure of this process is cleft palate).
Hearing
Behind that a pale cartilagenous region (that later ossifies) encloses the structuctures of the inner ear, beside which middle ear bones are forming. On the righthand side of the head the external ear is visible. The lower half of the image shows the developing brainstem with a large ventricular space occupied in part by an extensive choroid plexus (manufacturer of cerebrospinal fluid).
Embryonic External Ear
Shown below are the changes in external ear development between week 5 to week 8. Development changes from a series of 6 hillocks on arch 1 and arch 2 (week 5) to a structure resembling the adult ear (week 8).
| 2011 Lab 10: Introduction | Early Embryo | Late Embryo | Fetal | Postnatal | Abnormalities | Online Assessment |
