Chapter 8 (test 2) Flashcards
axial skeleton
skull, vertebral column, sternum, ribs, and hyoid
appendicular skeleton
pectoral girdle, upper limbs, hip bones and lower limbs
Number of bones and variations
Birth: 270 Adult: 206 Variation: -sesamoid bones develop in tendons - sutural bones
Sinuses
Paranasal Sinuses are the ethmoid, sphenoid, maxillary, and fontal
- mucous membrane lining and air filled
- lighten anterior portion of skull
- adds resonance to the voice
Cranial Bones and the cranium
Cranium protects the brain and associated sense organs - meninges separate the brain from direct contact with the bones 8 cranial bones -1 frontal -2 parietal -2 temporal -1 occipital -1 sphenoid -1 ethmoid
sutures
lines running between the cranial bones where they connect
foramina
holes for nerves and blood vessels
Facial Bones
-support teeth
-gives shape and individuality to face
-form point of orbital and nasal cavities
-attachments for muscles of facial expression and mastication
14 bones
-2 maxillae
-2 palatine bones
-2 zygomatic bones
-2 lacrimal bones
-2 nasal bones
-2 inferior nasal conchae
-1 vomer
-1 mandible
Bones associated with the skull
auditory ossicles
- 3 inner ear bones: malleus, stapes, and incus
hyoid bone
-supports the tongue
frontal bone
forehead and part of roof of cranium
- coronal suture: connects frontal bone to parietal bones
- supraorbital margin and supraorbital foramen
- contains frontal sinus
Parietal Bones
most of cranial roof and part of its lateral walls
-bordered by all four sutures
-sagittal: between the parietal bones
-coronal: between the frontal and parietal bones
-lambdoid: between the parietal and occipital bone
-squamous: between the temporal and parietal
2 temporal lines= attachment of temporalis muscle
Temporal Bones
Lateral wall and part of floor of cranial cavity
- zygomatic process
- mandibular fossa
- external auditory meatus
- internal auditory meatus: opening for vestibulocochlear nerve
- masstiod process and mastiod notch
Occipital Bone
Rear and base of skull
- foramen magnum- opening for the spinal cord
- skull rests on occipital condyles
- external occipital protuberance for nuchal ligament
Sphenoid bone
Optic foramen
sella turcica: houses pituitary gland
sphenoid sinus
-butterfly shaped bone touching the occipital and temporal bones
ethmoid Bone
located between the eyes
-perpendicular plate: superior 2/3 of nasal septum
Cribriform (olfactory) foramina
labyrinth with ethmoidal cells=ethmoid sinus
superior and middle nasal conchae: create turbulent airflow
Maxilla
Intermaxillary suture aveolar processes: bony points between teeth alveolus: sockets holding teeth palate: allows chewing while breathing -palatine process maxillary process
palatine bones
l-shaped bones
-horizontal plate
-perpendicular plate
posterior portion of hard palate
Zygomatic Bones
forms angles of cheek bones and part of lateral orbital wall
-zygomatic arch: from temporal process of zygomatic bone and zygomatic process of temporal bone
Lacrimal Bones
froms part of medial wall of each orbit smallest bones of the skull lacrimal fossa with lacrimal sac -tears collect in lacrimal sac--> nasal cavity located behind the eyes
Nasal Bones
bridge of nose
supports cartilages shaping lower portion of nose
often fractured by blow to nose
Inferior Nasal Conchae
3 conchae in nasal cavity
-superior and middle: part of ethmoid bone
Inferior nasal concha: a separate bone
Vomer
Inferior 1/2 of nasal septum
supports cartilage forming anterior part of nasal septum
Mandible
strongest bone of skull -supports lower teeth alveo;ar processes mental foramen mandibular condyle and TMJ mandibular foramen
Functions of the vertebral column
- supports skull and trunk
- allows for their movement
- protects the spinal cord
- absorbs stress of walking, running, and lifting
- provides attachments for limbs, thoracic cage, and postural muscles
Vertebral Column
33 vertebrae all together 5 groups -7 cervical in neck -12 throracic in chest -5 lumbar in neck -5 fused sacral -4 fused coccygeal
Vertebral Curvatures
1 curve at birth as an adult 4 normal curvatures -cervical (at birth) -thoracic (by the time a kid can sit) -lumbar (by the time a kid can walk) -pelvic
Vertebra
Body -mass of spongy bone contains red bone marrow -covered with thin shell of compact bone -Function: weight bearing portion vertebral foramina: vertebral canal for spinal cord vertebral arch -pedicle: pillarlike -lamina: platelike spinous process -from apex of arch transverse process superior articular processes -meets inferior articular processes Facets -flat articular surfaces covered with hyaline cartilage Intervertebral foramen -opening between 2 vertebrae -for spinal nerves
Intervertebral Discs
1st between C2 and C3 last between L5 and sacrum 2 parts -nucleus pulposus: inner gelatinous mass -anulus fibrosus: outer ring of fibrocartilage binds the vertebrae together bupports body weight absorbs shock
C1 or Atlas
supports the head no body superior articular facets -nodding motion atlanto-occipital joint: between atlas and occipital bone(cranium) inferiorarticular facets
C2 or Axis
allows for the rotation of the head dens/odontoid process -vertebral foramen of atlas -transverse ligament Atlantoaxial joint: between the atlas and axis
cervical vertebrae
bifid or forked spinous processes C2-C6
small body and larger vertebral foramen
transverse foramen in transverse process
-passage and prtection of vertebral arteries and veins
-only in cervical vertebrae
C7 vertebra prominens: spinous process not bifid and very long
thoracic vertebrae
12 vertebrae -the pairs of ribs attach spinous processes: pointed and angled sharply down body: >cervical, but <lumbar costal facets: rib attachment -transverse costal facets (T1-T10) -inferior and superior costal facets
Lumbar Vertebrae
5 vertebrae body: very large and thick spinous process: blunt and square superior articular processes: face medially -resistes to twisting movements
Sacrum
5 fused 4 transverse lines anterior and posterior sacral foramina sacral promontory: on S1, supports S5 superior articular processes on S1 auricular surface
Coccyx
4 small fused horns on Co1 -attachment for ligaments binding coccyx to sacrum attachment for muscles of pelvic floor fractured -difficult childbirth -hard fall on butt
Thoracic Cage
Thoracic vertebrae, 12 pairs of ribs, sternum
attachment for pectoral girdle and upper limbs
respiratory muscles expand
protect thoracic organs, spleen and most of liver and some kidneys
sternum
breastbone 3 regions -manubrium(clavicular notches) -body -xiphoid process --abdominal muscle attachment --improper CPR=fatal hemorrage
Ribs
12 pairs -anterior(distal) end -posterior(proximal) end -costal cartilage: hyaline cartilage attach to the anterior end to sternum Head -superior articular facet -inferior articular facet Tubercle -articular facet True Ribs: 1-7 -own cartilage connecting directly to the sternum False Ribs: 8-12 -8-10: cartilage connects to other cartilage -11-12: floating ribs (no cartilage)
Pectoral girdle (shoulder girdle)
clavicle and scapula
- clavicle articulates
- -medially to sternum (sternoclavicular)
- -laterally to scapula (acromioclavicular joint)
- scapula articulates with
- -humerus (glenohumeral joint)
- -loose attachment= easily dislocated
Clavicle
sternal end
acromial end
braces shoulder, keep upper limb away from midline of body
scapula
acromion
coracoid process: biceps muscle tendon attachment
glenoid cavity
spine
humerous
head articulates with glenoid cavity of scapula deltoid tuberosity capitulum trochlea lateral and medial epicondyles olecranon fossa coronoid fossa radial fossa
Radius
Head: disc shaped, allows rotation -articulates with capitulum on humerous -articulates with radial notch on ulna styloid process ulnar notch
Ulna
Trochlear notch articulates with of humerus olecranon coronoid process radial notch styloid process interosseous membrane -ligament attaches radius to ulna -two elbow joints share the load
Carpal Bones
8 bones in the wrist -Flexion, extension, abduction, and adduction Proximal Row: (in order from lateral to medial) -scaphoid -lunate -triquetrum -pisiform (sesamoid) Distal Row: (in order from medial to lateral) -hamate -capitate -trapezoid -trapezium
Pelvic Girdle
2 hip bones and sacrum
Pelvis: pelvic girdle, ligaments and muscles
-supports trunk on lower limbs
-protects viscera
interpubic disc
fibrocartilage joins pubic bones
Pubic symphysis
interpubic disc and regions of pubic bone on each side
pollex
the thumb
hallux
big toe
Hip Bone
iliac crest: superior crest of hip
acetabulum: hip socket
obturator foramen: large hole below acetabulum
adult hip bone: fusion of the ilium, ischium and pubis
Ileum
Greater sciatic notch
sacroiliac joint: auricular surface if ileum to auricular surface of sacrum
Ischium
ischial tuberosity (where we sit)
Pubis (pubic bone)
houses the urinary bladder
