renaissance dental to the embryo during the second and third weeks the disc develops three circular sheets called primary germ layers renaissance dental from which all body structures will derive so that’s some animals don’t have three germ laye.
rs we can see them here so here is the endoderm amee’s enter and you have the amniotic cavity the embryonic disk Danielle sac the implantation scar
the trophoblast the maternal blood sinus and here at all taking place within the endometrium fetal development so
why don’t we just go through these weeks eight to ten the fetuses crown rump head and body length is five to six centimeters so t
o the tune a half inches and it’s heart rate rate is a hundred and seventy two hundred and eighty beats per minute head growth is slowing the
neck lengthens and the head lifts from the chest and the kidneys start to function at the end of week week t