Two years into an Arctic expedition, they were forced to abandon ship a thousand miles north of Siberia. The Best Nonfiction Books of 2014 William OâConnor December 14, 2014 Going to the library was like a treasure hunt, an expedition.
The vertebral column, also known as the backbone or spine, is part of the axial skeleton. The vertebral column is the defining characteristic of a vertebrate, in which the notochord (a flexible rod of uniform composition) found in all chordates has been replaced by a segmented series of bonesâvertebrae separated by intervertebral discs.
The first seven vertebrae form the cervical spine. The mid back, called the thoracic spine, consists of 12 vertebrae. The lower portion of the spine, called the lumbar spine, is usually made up of five vertebrae. However some people have a sixth lumbar vertebra. The normal spine has an S-like curve when looking at it from the side.