Stage |
Days |
Event
|
10
|
8.5 |
First somites appear, rostral neuropore closes
|
12
|
9.5 |
Rostral limb bud, embryonic pedicle, caudal neuropore closes, one cerebral vesicle, pharyngeal arches, completion of optic vesicle
|
13
|
10.5 |
Dosral C-shaped curvature, caudal limb bud, prominent cardiac swelling, four pharyngeal arches
|
|
14
|
11.5 |
Three cerebral vesicles, optic plate, mesonephric ridge
|
15
|
12.5 |
Hand plate, wheel ray limbs, lens vesicle closes, five cerebral vesicles, facial buds, vertebrae
|
|
16
|
13.5 |
Foot plate, finger rays, prominent liver, intestinal loops, auricular hillocks
|
|
19
|
14.5 |
Cuboidal body, trunk straightens, parallel limbs, toe rays, modeled face, visible auricle
|
|
20
|
15.5 |
Elbow, fingers elongate, notches between toe rays
|
|
21-22
|
16.5 |
Toes free, cecal bud in intestinal hernia
|
|
22-23
|
17.5 |
Knee, neck, eyelids
|
|
23
|
18.5 |
Hands and feet join at the midline, closure of abdominal wall, eyelids cover eyes
|
|
Following this stage fetal appearance is completed, organogenesis is achieved
|