axial skeleton Flashcards
structures of bones include
- articulations
- landmarks
- foramina
what type of structure indicate contacts with other bones?
articulation
what type of structure indicate areas of muscle and ligament attachment?
landmarks
what type of structure indicate openings for nerves and blood vessels?
foramina
Axial Skeleton
Forms the longitudinal axis of the body
how many bones does skull have?
- 8 cranial bones
- 14 facial bones
Bones associated with the skull
- 6 auditory ossicles
- The hyoid bone
bones in vertebral column
- 24 vertebrae (singular = vertebra)
- The sacrum
- The coccyx
bones in thoracic cage
- 24 ribs
- The sternum
function of axial skeletion
- Attaches to muscles of head, neck, and trunk
- Performs respiratory movements
- Stabilizes parts of appendicular skeleton
what does the skull protect?
- The brain
- Entrances to respiratory system
- Entrance to digestive system
function of facial bones
Protect and support entrances to digestive and respiratory tracts
Cranial Bones
- Enclose the cranial cavity
- Which contains the brain
Facial Bones
have 2 parts:
- superficial facial bones
- deep facial bones
superficial facial bones
muscle attachment
deep facial bones
Separate the oral and nasal cavities
which type of facial bone will form nasal septum?
deep facial bones
sinuses
Cavities that decrease the weight of the skull
which cavity lined with mucous membrane and protect entrance of respiratory system?
sinuses
sutures
The immovable joints of the skull
four major sutures
- Lambdoid suture
- Coronal suture
- Sagittal suture
- Squamous suture
lambdoid suture
separates the occipital from the parietal bone
which type of suture contain sutural bone?
lambdoid suture
sagittal suture
- between parietal bones
- from lambdoid suture to coronal suture
squamous suture
Form boundaries between temporal bones and
parietal bones
Coronal Suture
Attaches frontal bone to parietal bones
calvaria (skullcap)
Consists of occipital, parietal, and frontal bones
types of cranial bones
- Occipital bone
- Parietal bones
- Frontal bone
- Temporal bones
- Sphenoid
- Ethmoid
types of bone in occipital bone
- foramen magnum
- occipital condyles
foramen magnum
connects cranial and spinal cavity
Functions of the temporal bones
- Part of lateral walls of cranium and zygomatic
arches - Articulate with mandible
- Surround and protect inner ear
- Attach muscles of jaws and head
Auditory Ossicles
Three tiny bones in tympanic cavity (middle ear)
sound transfer from _________ ____________ to
__________ ______
tympanic membrane (eardrum) to
inner ear
_________ _________support the lower teeth
Alveolar processes
Mental protuberance
attaches facial muscles
Marks of the mandible
- body
- alveolar processes
- mental protuberance
infant skull
- grow rapidly
- relatively large to body
what kind of ossification does infant skull have?
intramembranous ossification
does infant skull completed?
fusion is not complete at birth
Fontanelles
areas of fibrous connective tissue (soft spots)
which structure cover unfused sutures in the infant skull ?
fontanelles
which structure allow skull to flex at birth?
fontanelles
4 types of fontanelles
- Anterior Fontanelle
- Occipital Fontanelle*
- Sphenoidal Fontanelles*
- Mastoid Fontanelles*
which types of fontanelles will disappear 1-2 months old?
*Occipital, sphenoidal, and mastoid
Anterior fontenelle
Frontal, sagittal, and coronal sutures
abnormalities of cranial growth
- craniostenosis
- deformational plagiocephaly
Craniostenosis
- Premature closure of fontanelle
- Unusual distortions
Deformational Plagiocephaly
Repeated pressure on the same area
how many bones does vertebral column have?
total 26
- 24 vertebrae
- sacrum
- coccyx
how many vertebrae does the neck have?
7 cervical vertebrae
how many vertebrae does the upper back have?
12 thoracic vertebrae
what does thoracic vertebrae associate with?
Each articulates with one or more pair of ribs
how many vertebrae does the lower back have?
5 lumbar vertebrae
which vertebrae associate with sacrum?
5th lumbar vertebra
which structure articulate with coccyx?
sacrum
4 spinal curves
- Cervical curve
- Thoracic curve
- Lumbar curve
- Sacral curve
which vertebra region is the spinous process of vertebra prominens?
C7
which cervical vertebrae has no spinous process?
C1 (atlas) -> yes
C2 vertebra
axis -> no
what does sacrum attach to?
- The axial skeleton to pelvic girdle
- Broad muscles that move the thigh
what does adult sacrum consist of?
five fused sacral vertebrae
which structure attaches ligaments and anal sphincter?
coccyx
what does mature coccyx consist of?
three to five (typically 4) fused
coccygeal vertebrae
what strucutre does thoracic cage support ?
thoracic cavity: thoracic vertebrae, ribs, sternum
Pectoral Girdle consist of:
- clavicles – (2)
- Scapulae – (2)
what type of bone does arm (branchium) have?
humerus
which structure does humerus articulate with?
pectoral girdle
