7B.2 Flashcards
How many bones does the axial skeleton have?
80 bones
How many bones does the skull have?
22 bones
The skull (different parts)
*most use sutures for joints (sagital, coronal, lamboid, squamous)
*The mandible (lower jaw) and auditory ossicles are not sutured and are moveable
*Made up of the cranial and facial bones
How many bones is the cranium?
8 bones
The cranium
*encloses and protects the brain
*surface of the attachment for chewing and head movements
*contain air-filled cavities called paranasal cavities
- lined with mucus membranes
- reduce skull weight and serves as a resonant sound chamber
*besides the cranial cavity there are smaller cavities that open to the external nasal cavities and orbits (eye sockets)
Cranial bones
- Frontal bone
- Parietal bones
- Occipital bone
- Temporal Bones
How many frontal bones are there
1 : )
Frontal bone
*1 bone
*supraorbatial foramen- blood vessels and nerves for forehead
*2 frontal sinuses
Parietal bones
*2 bones
*fused at the sagittal and coronal sutures (R & L)
Occipital bone
*1 bone
*fused at the lamboid suture
*foremen magnum: hole for spinal cord to connect with brainstem
Temporal bone
*2 bones
*Has external auditory meatus- hole leading to inner ear
- 2 major processes for muscle attachment
- Mastoid process: muscles of the neck
-Styloid process: muscles dealing with tongue and pharynx (throat)
*helps form the cheek bone= zygomatic process
What are the 2 major processes for muscle attachment
*Mastoid process and Styloid process
Sphenoid bone
*1 bone
*Has 2 sphenoidal sinuses
*Wing-like structure that forms base of cranium
Ethmoid bone
*1 bone
*found in front of sphenoid and form the nasal septum= divides right and left nostril
*Nasal conchae= project inwward and support mucus membranes lining the nasal cavity
*many small air spaces called ethmoidal sinuses
