Skeletal System Flashcards
What are the functions of bones?
- providing an internal framework
- protecting vital organs
- attachment site for muscles
- storing calcium phosphate (inorganic salts)
- hematopoiesis (blood cell formation)
- storing fat in the yellow bone marrow
What are the bones of the axial skeleton?
- skull
- hyoid bone
- vertebral column
- thoracic cage
What are the bones of the appendicular skeleton?
- 2 pectoral girdles each with a scapula and clavicle
- 2 upper limbs each with a humerus, radius, ulna, carpals, metacarpals and phalanges
- 2 pelvic girdles each made of a coxal bone
- 2 lower limbs each with a femur, tibia, fibula, patella, tarsals, metatarsals and phalanges
What does the vertebral column consist of?
cervical, thoracic, lumbar, sacral, and coccygeal vertebrae
What does the thoracic cage include?
the ribs and the sternum, thoracic vertebrae and costal cartilages
What bones does the skull consist of?
cranial bones and facial bones
What are 2 functions of the cranium?
- support and protect the brain and special sense organs
- provide an attachment site for facial muscles
List the 8 cranial bones.
- frontal bones (form the forehead)
- 2 parietal bones (are posterior to the frontal bone and form a portion of the sides & roof of the cranial cavity)
- 2 temporal bones (form the lower lateral sides of the head and enclose the internal structures of the ear)
- occipital bones (form the posterior portion of the head)
- sphenoid bone (a bat shaped bone that forms a portion of the cranial cavity floor)
- ethmoid bone (an irregularly shaped bone that forms a portion of the cranial cavity floor, nasal cavity walls, nasal septum and eye orbits)
What are the 4 paranasal sinuses?
- frontal: are air-filled cavities above the eye orbits
- sphenoidal: air-filled cavity behind the nasal cavity
- ethmoidal: air-filled cavity in the lateral portions of the bone
- maxillary: air filled cavities lateral to the nasal cavity
What is the function of the paranasal sinuses?
warm and moisten inspired air and give resonance to the voice
What are the four major sutures that unit most of the cranial bones?
coronal suture: unites the frontal bone and the parietal bones
sagittal suture: unites the 2 parietal bones
lambdoidal suture: unites the parietal bones and occipital bones
squamosal suture: unites the parietal bones and the temporal bones
What are the 14 facial bones in the skull?
- 2 maxillae: form a portion of the walls and floor of the nasal cavity and contain the sockets for the top teeth
- 2 palatine bones: form the posterior portion of the nasal cavity floor
- 2 zygomatic bones: form the cheekbones
- 2 lacrimal bones: form a portion of the eye orbits
- 2 nasal bones: form the bridge of the nose
- 1 vomer bone: form the inferior portion of the nasal septum
- 2 inferior nasal concha: form the inferior lateral ridges in the nasal cavity
- 1 mandible: only moveable skull bone, forms the lower jaw and contains sockets for the bottom teeth
What are the functions of the vertebral column?
- support the head and trunk
- protect the spinal cord
- serving as the site of attachment for the ribs and muscles of the back
What are the basic features of the vertebra?
body: supports the weight of the body
spinous process: sites of attachment for ligaments and muscles
transverse process: site of attachment for ligaments and muscles
vertebral foramen: allows the spinal cord to pass through the vertebra
How many vertebrae does the cervical vertebrae have in total?
7
- the atlas: the first cervical vertebrae, a ring of bone that supports the skull
- the axis: the second cervical vertebrae, has a tooth like peg called the odontoid process on which the atlas rotates
- the transverse process have transverse foramen through which arteries pass to the brain. These arteries are called vertebral arteries
How many vertebrae does the thoracic vertebrae have in total?
12
- the bodies are larger then the cervical vertebrae
- most have 6 costal facets, 4 on the body and 2 on the transverse process for rib attachment
- the spinous process of the thoracic vertebrae are long, pointed and slope downward
How many vertebrae does the lumbar vertebrae have in total?
5
-the bodies of the lumbar vertebrae are square and sturdy with blunt spinous processes, as these vertebrae support the most weight. There are NO costal facets on these vertebrae
How many vertebrae does the sacral vertebrae have in total?
5
- these are formed together to form the sacrum
- the sacrum is a triangular shaped structure
- the sacrum contains 4 pairs of openings called sacral foramen for the passageway of nerves and blood vessels