. Human embryology and morphology. Embryology, Human; Morphology. 100 HUMAN EMBRYOLOGY AND MORPHOLOGY. transverse section of the body-stalk shows within it the same elementary structures as are seen in a transverse section of the embryo. The cord must be regarded as a real part of the embryo. The umbilicus, which marks the point of attachment of the cord, is situated in the adult on the ventral surface, but before it was thrust into this position by the development of the caudal and perineal regions of the body, it represented the posterior termination of the embryo (Figs. 74 and 75). The amni
. Human embryology and morphology. Embryology, Human; Morphology. 100 HUMAN EMBRYOLOGY AND MORPHOLOGY. transverse section of the body-stalk shows within it the same elementary structures as are seen in a transverse section of the embryo. The cord must be regarded as a real part of the embryo. The umbilicus, which marks the point of attachment of the cord, is situated in the adult on the ventral surface, but before it was thrust into this position by the development of the caudal and perineal regions of the body, it represented the posterior termination of the embryo (Figs. 74 and 75). The amniotic somatopleure rises from the sides of the body-stalk and encloses it just as it rises from, and encloses, the embryo (Fig. 72), and, as is shown in the next paragraph, the lateral folds of the somatopleure unite in the ventral line of the body-stalk as in the ventral line of the belly (Fig. 78).. mmon cauity of amnion (continuation of medullary yrooue umb. veins -somatopleure umb. artery coelom •cauity of allantois Vitelline duct. Fig. 7S.—Diagrammatic section showing the structures which go to form the Umbilical Cord. (After His.) Transverse Section of the Umbilical Cord (Fig. 78). A section of the cord shows : (1) Two umbilical arteries (continuations of the primitive dorsal aortae). (2) One umbilical vein, formed by the fusion of the two original veins. (3) The cavity of the allantois formed from the hind gut. Within the cord its lumen becomes obliterated early. (4) The vitelline duct, the stalk of the yolk sac, communica- ting with the intestine and yolk sac. It becomes obliterated in the 3rd Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Keith, Arthur, Sir, 1866-1955. London : E. Arnold
Size: 1463px × 1708px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
