Chapter 6 Axial Division Flashcards
How many bones are in the axial skeleton, and what are its three major regions?
The axial skeleton consists of 80 bones. The three major regions are the skull, the vertebral column, and the thoracic cage.
Name the eight cranial bones.
Frontal bone, parietal bones (2), occipital bone, temporal bones (2), sphenoid bone, and ethmoid bone.
What are the four main sutures of the skull, and where are they located?
Coronal Suture: Between the frontal and parietal bones.
Sagittal Suture: Between the two parietal bones.
Lambdoid Suture: Between the parietal bones and occipital bone.
Squamous Suture: Between the parietal and temporal bones.
How many cervical vertebrae are there, and what is unique about the first two?
There are 7 cervical vertebrae. The first vertebra, atlas (C1), supports the skull and allows nodding movements. The second vertebra, axis (C2), has the dens, which allows head rotation.
What is the difference between true ribs, false ribs, and floating ribs?
True Ribs (1-7): Attach directly to the sternum via costal cartilages.
False Ribs (8-10): Attach to the sternum indirectly via the cartilage of the 7th rib.
Floating Ribs (11-12): Do not attach to the sternum at all.
What are the three parts of the sternum?
The three parts of the sternum are the manubrium, the body, and the xiphoid process.
What are the primary and secondary curves of the spine, and when do they develop?
Primary Curves: Thoracic and sacral curves, present at birth.
Secondary Curves: Cervical and lumbar curves, which develop after birth to support the head and walking.
What bone in the axial skeleton does not articulate directly with any other bone, and what is its function?
The hyoid bone does not articulate directly with any other bone. It supports the tongue and serves as an attachment site for muscles of the larynx, pharynx, and tongue.
Describe the function of the thoracic cage.
The thoracic cage protects vital organs like the heart and lungs, supports the shoulder girdles and upper limbs, and assists in respiration by facilitating lung expansion.
What is the function of the foramina in the skull?
The foramina are openings in the skull that allow the passage of nerves and blood vessels to and from the brain.
