. Die chordates. Chordata. 136 Grundlegende Struktur der Wirbeltiere. Abb. 129. Tails von Fischen. (A) Die jungen Amia. (H) Hypurals; (n): Chorda dorsalis; (s) des Rückenmarks. (B) Diphycercal. (C) Heterocercal. (D) Homocercal. (Höflichkeit, Kingsley: "vergleichenden Anatomie der Wirbeltiere", Philadelphia, die Blakiston Company.) Skelettmuskulatur Achsen in Beschreibungen der Wirbeltiere Skelett, es ist der Gemeinsame prac-tice zum "axialen Skelett" als bestehend aus der Wirbelsäule col-Umn, Schädel, Rippen und Brustbein - das heißt, das gesamte Skelett ist "axial", ausgenommen solche Teile, die die "appe dar

• Bildanbieter: Library Book Collection / Alamy Stock Foto
• Bild-ID: RJ5M3T
• Dateigröße: 7,1 MB (306,5 KB Komprimierter Download)
• Freigaben (Releases): Model - nein | Eigentum - nein
• Format: 2050 x 1219 px | 34,7 x 20,6 cm | 13,7 x 8,1 inches | 150dpi

Weitere Informationen

Dieses Bild ist ein gemeinfreies Bild. Dies bedeutet, dass entweder das Urheberrecht dafür abgelaufen ist oder der Inhaber des Bildes auf sein Urheberrecht verzichtet hat. Alamy berechnet Ihnen eine Gebühr für den Zugriff auf die hochauflösende Kopie des Bildes.

Dieses Bild kann kleinere Mängel aufweisen, da es sich um ein historisches Bild oder ein Reportagebild handel

. The chordates. Chordata. 136 Basic Structure of Vertebrates. Fig. 129. Tails of fishes. (A) Young Amia. (h) Hypurals; (n) notochord; (s) spinal cord. (B) Diphycercal. (C) Heterocercal. (D) Homocercal. (Courtesy, Kingsley: "Comparative Anatomy of Vertebrates, " Philadelphia, The Blakiston Company.) Skeletal Axes In descriptions of the vertebrate skeleton, it is the common prac- tice to define the "axial skeleton" as consisting of the vertebral col- umn, skull, ribs, and sternum—that is, the entire skeleton is "axial " except such parts as constitute the "appendicular skeleton." Some authors make three divisions of it—axial, visceral, and appendicular. In either case, "axial" obviously refers to the vertebral or notochordal axis. The division of the skeleton into two parts, axial and appendicu- lar, has the virtue of simplicity, but otherwise it seems inadequate and lacking in significance. The vertebrate body has more than one axis. Built on the "tube- within-a-tube" plan (see p. 23 and Fig. 16), the inner or alimentary tube establishes a visceral axis. The elongated coelom has a coelomic axis. If the digestive tube, straightened out, is regarded as being the central organ in the coelom, the visceral and coelomic axes coincide. The basic structural—i.e., "architectural"—axis of the animal-as-a- whole is the axis of the inner tube, the visceral axis. (Nutrition is certainly the basic physiologic axis of the animal!) But, regarding the body as a dynamic thing, its chief mechanical axis is occupied by the vertebral column which is situated in the dorsal body-wall, whose heavy musculature effects the major movements of the body. The visceral arches develop around the alimentary tube. They are "axial, " but it is in relation to the visceral axis. It is true that the dorsal part of the first visceral arch becomes secondarily joined to the floor of the cranium. But, in doing so, the bone

Stockbilder mithilfe von Tags suchen

• bookcentury1900
• bookcollec