Hamilton, Boyd and Mossman's Human Embryology: Prenatal Development of Form and Function

abnormal activity amniotic AORTA appears arch arise arteries aspect associated attached becomes blood body bone called canal cartilage caudal cavity cells changes chorion chromosomes COELOM complete continuous cord cranial cytoplasm definitive derived differentiation division dorsal duct early ectoderm eggs embryo endoderm epithelium established extends external female fetal fetus fibres formation functional fuse give glands groove grows growth heart hormones human human embryo increase later layer length lower male mammals maternal membrane mesenchyme mesoderm mesonephric month muscle nerve neural neural tube normal occurs optic organs origin pass period persists pharyngeal placenta plate portion posterior pregnancy present primary primitive produced region result separated septum shown side sinus somites soon space stage structure surface third tissue trophoblast tube types umbilical urogenital sinus usually uterine VEIN ventral VENTRICLE vertebrates vesicle vessels wall yolk sac