Though not really part of the skull closely related to the mandible and

Though not really part of the skull closely related

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Though not really part of the skull, closely related to the mandible and temporal bones, horseshoe shaped only bone in the body that does not articulate directly with any other bone suspended midneck region above the larynx, anchored by ligaments to the styloid process serves as a movable base for the tongue and neck muscles Fetal Skull Cranium is very small in a baby, ¼ of its body Some areas of hyaline cartilage remain to be ossified Fontanels- In a newborn, the skull also has fibrous regions that connect the cranial bones Rhythm of a baby’s pulse can be felt in these spots Allow the fetal skull to be compressed slightly during birth, allow the baby’s brain to grow in the later part of pregnancy Vertebral Column before birth, the spine consists of 33 separate bones called vertebrae o 9 of these bones eventually fuse to form 2 composite bones- the sacrum and coccyx o 24 single bones 7 vertebrae of the neck- cervical vertebrae 12- thorarcic vertebrae 5- lumbar vertebrae- supporting the lower back intervertebral discs- individual vertebrae are separated by flexible fibrocartilage that cushion the vertebrae and absorb shock while allowing spine flexibility o discs have a high water content when young, decreases as ages Curvatures o primary curvatures- spinal curvatures in the thoracic and sacral region present when we are born, “C-shaped” spine o secondary curvatures- cervical & lumbar regions, develop after birth o Abnormal Spinal Curvatures Scoliosis, kyphosis, lordosis All Vertebrae have a similar structural pattern- Body- disklike, weight bearing part of the vertebra facing anteriorly in the vertebral columns Vertebral Arch- arch formed from the joining of all posterior extensions o Laminae & pedicles form the vertebral body Vertebral Foramen- canal through which the spinal cord passes Transverse Process- 2 lateral projections from the vertebral arch Spinous process- single projection arising from the posterior aspect of the vertebral arch Superior & inferior articular process- paired projections lateral to the vertebral foramen, allowing a vertebra to form joints with adjacent vertebrae Cervical Vertebrae 7 cervical vertebrae form the neck region of the spine 1 st 2 vertebrae ( atlas & axis) o Atlas (C1) has no body, superior surfaces of its transverse processes contain large depressions that receive the occipital condyles o Axis (C2) acts as a pivot for the rotation of the atlas and skull above has a large upright process, the dens, which acts as the pivot point the joint between the C1 and C2 allow you to rotate your head from side to side typical cervical vertebrae, are the smallest, lightest vertebrae
o most often their spinuous processes are short and divided into 2 branches o transverse processes of the cervical vertebrae contain foramina (openings) through which the vertebral arteries pass their way Thoracic Vertebrae 12 thoracic vertebrae, larger than the cervical vertebrae and are distinguished by the fact that they are

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