Seven functional components of the cranial nerves general somatic efferen eye(Ⅲ，V、I)and tongue(Ⅻ) 99888 >general visceral efferen fiber travel within III,VII,IX,X special visceral efferent 88 the branchial arches involved in swallowing (IX.X),producing v Fish Salamander Tortoise Chick Hog Calf Rabbit Human FIGURE 1.The appearance of ertebrate embryos at damental observation suggests that these different ani arious stages of development.The similarity of different mals share both a common ancestor and the same bas embryos during early development is striking;this fun-mechanisms of development.(From Romanes,1901.) general somatic efferent fiber (GSE): striated muscles involved in eye (Ⅲ , Ⅳ、Ⅵ ) and tongue (Ⅻ)  general visceral efferent fiber (GVE): preganglionic parasympathetic fiber travel within Ⅲ , Ⅶ, Ⅸ , Ⅹ  special visceral efferent fiber (SVE): striated muscles derived from the branchial arches involved in chewing (Ⅴ), making facial expressions (Ⅶ ), swallowing (Ⅸ、Ⅹ), producing vocal sounds (Ⅹ) and turning the head (Ⅺ) Seven functional components of the cranial nerves