describe the structure of a typical vertebra
Answers
Explanation:
Vertebral column in general
The vertebral column usually consists of 33 vertebrae: 24 presacral vertebrae (7 cervical, 12 thoracic, and 5 lumbar) followed by the sacrum (5 fused sacral vertebrae) and the coccyx (4 frequently fused coccygeal vertebrae). The 24 presacral vertebrae allow movement and hence render the vertebral column flexible. Stability is provided by ligaments, muscles, and the form of the bones. The abbreviations C., T., L., S., and Co. are used for the regions, and these are sometimes followed by V. for vertebra or N. for nerve.
Curvatures.
The adult vertebral column presents four anteroposterior curvatures: thoracic and sacral, both concave anteriorly, and cervical and lumbar, both concave posteriorly (fig. 39-1). The thoracic and sacral curvatures, termed primary, appear during the embryonic period proper, whereas the cervical and lumbar curvatures, termed secondary, appear later (although before birth) and are accentuated in infancy by support of the head and by the adoption of an upright posture.
Parts of a Vertebra.
A typical vertebra consists of (1) a body and (2) a vertebral arch, which has several processes (articular, transverse, and spinous) for articular and muscular attachments. Between the body and the arch is the vertebral foramen: the sum of the vertebral foramina constitutes the vertebral canal, which houses the spinal cord