Data

Copy and paste the text below. It is read-only. Select All

germinal period 8-10 days implantation embryonic period 1.5-8 weeks task beginning of major organs (heart, cns, legs, ears, palate) ectoderm nervous system, teeth, nails, eyes, inner ear, outer layer of skin mesoderm muscles, bones, circulatory system, inner layers of skin endoderm digestive system and lungs fetal period 9 weeks through birth neurogenesis creation of new nerve cells from stem cells age of viability 22-28 weeks