vertebral column
vertebral column defined in 1951 year
vertebral column - vertebral column (spinal column);vertebral column - Backbone. Longitudinally arranged chain of small bones or cartilages (vertebrae) near dorsal side, surrounding spinal cord, characteristic of vertebrates. In most vertebrates (not cyclostomes) the vertebrae form a jointed hollow rod, attached to the skull in front, enclosing the spinal cord, and more or less replacing notochord during embryonic development. The mid-point of the length of each vertebra lies level with the interval between successive somites in the embryo. Each vertebra usually consists of a substantial mass (the centrum) where the notochord was, with an arch (neural arch) above enclosing the spinal cord and often a similar arch (haemal arch) below, or ventral projections, enclosing main axial blood-vessels. They are jointed to each other by their centra, and often by projections of the neural arch, though only restricted movement is possible between any two vertebrae. See also: Symphysis. In fish all vertebrae from skull to tail are very similar. But in tetrapods there are regional differences usually as follows: atlas and axis; neck (cervical) with reduced ribs; thoracic, bearing ribs; lumbar, again without ribs; sacral, attached by rudimentary ribs to pelvic girdle; and tail (caudal).
near vertebral column in Knolik
| vertebra | home letter "V" start from "VE" | vertebrata |
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