Description

This 3D model was generated based on segmentation of the stage 23 embryo from the Virtual Human Embryo Project. Details about this embryo, images, and further information can be found here: Virtual Human Embryo Stage (https://www.ehd.org/virtual-human-embryo/stage.php?stage=23)16 (https://www.ehd.org/virtual-human-embryo/stage.php?stage=16) The description provided for the embryo is as follows: Stage 16 embryos have a greatest length of 8 to 11 mm and an estimated postfertilization age of 39 days. The retinal pigment is distinct and the foot plate has formed. The stage is represented by Carnegie embryo #6517 that has a grade of excellent. It is considered to be the best specimen in the Carnegie collection at this stage. It has a greatest length of 10.5 mm (after fixation) and is considered to be in the most advanced third of the stage. The embryo was prepared for microscopic examination around 1931. It was fixed in corrosive acetic acid, embedded in celloidin and paraffin and serially sectioned transverse to the long axis at 8 microns. The sections were mounted on 46 large glass slides and stained with alum cochineal (carmine). There are 1103 sections through the embryo.