Skeleton Flashcards
how many bones in the axial skeleton
80
how many bones in the skull
22
how many cranial bones
8
how many facial bones
14
what are the cranial bones
2 parietal (top); 2 temporal (sides); 1 frontal (front); 1 occipital (back); 1 sphenoid (eye orbit); 1 ethmoid (nasal area)
temporal bone
zygomatic process – supports cheek;
mandibular fossa – rounded depression on the inferior surface of the zygomatic process and forms the socket for the mandibular condyle, the point where the mandible joins the cranium;
styloid process – attach muscles for speaking and swallowing;
external auditory canal – ear canal;
mastoid process – attach neck muscles
occipital bone
foramen magnum – large opening for spinal cord;
occipital condyles – articulate with vertebral column (atlas)
sphenoid bone
greater wings – form part of eye orbit;
lesser wings – provide anchoring site for dura mater;
sella turcica – depression where the pituitary gland is found;
optic canals – allow passage of optic nerves
ethmoid bone
perpendicular plate – forms superior part of nasal septum;
cribiform plate – contains tiny holes for passage of olfactory nerves;
crista galli – provides point of attachment for the dura mater, helping to secure the brain within the skull
paranasal sinuses
cavities in frontal, ethmoid, sphenoid, and maxillary bones; contain sinuses; all help to lighten weight of the skull, and all are lined with mucous membrane to help filter incoming air and trap particles
what are in the facial bones
2 maxillary (upper jaw); 2 palatine (hard palate); 2 zygomatic (cheek); 2 lacrimal (eye orbit; contain lacrimal or tear glands); 2 nasal (bridge of nose); 2 inferior nasal conchae (nostrils); 1 vomer ( part of nasal septum); 1 mandible (lower jaw; only movable bone in skull; mandibular condyles – articulation point of mandible with the mandibular fossa of the temporal bone thus forming the tempero-mandibular joint
sutures of the skull
immovable joints; coronal (frontal/parietal); lambdoidal (occipital/parietal); sagittal (parietal/parietal); squamosal (parietal/temporal)
auditory ossicles
bones in middle ear; Hammer (Maleus); Anvil (Incus); Stirrup (Stapes)
hyoid
movable (speech & swallowing); located in throat above the larynx; does not directly attach to any other bone; serves as point of attachment for many tongue and neck muscles
vertebral column
7 cervical; 12 thoracic; 5 lumbar; 1 sacrum; 1 coccyx;
4 normal curves
forward cervical
backward thoracic
forward lumbar
backward sacral
{backward curves are primary curves (present in fetus)}
what are 3 possible abnormal vertebral curvatures
- scoliosis
- kyphosis
- lordosis
scoliosis
abnormal lateral curve, most often in the thoracic region; particularly
among adolescent girls; can be corrected with a back brace
kyphosis
(hunchback) – an exaggerated thoracic curvature
lordosis
(swayback) – an exaggerated lumbar curvature
structure of a vertebra
body (supports weight);
vertebral or neural arch (protects spinal cord);
spinous process (attachment of soft tissue);
transverse processes (attachment of soft tissue)
sternum
manubrium (articulates with clavicle);
body (main part);
xiphoid process (soft tissue attachment);
manubriosternal joint (moves during inhalation);
sternal puncture (test for anemia; highest % of RBC in sternum)
ribs
true or vertebrosternal (1-7) – attach directly to sternum;
false or vertebrochondral (8-10) - indirectly attach to sternum;
floating (11-12) – do not attach to sternum; all ribs attach to vertebral column
structure of a rib
head (attaches to vertebral column);
neck (short & flattened); tubercle (articulates with transverse process of vertabra);
shaft or body (longest part; may attach to sternum)
how bones in the appendicular skeleton
126
what makes up the pectoral girdle
Clavicle (2) - collarbone
Scapular (2) – shoulder-blade; triangular body;
•spine on posterior surface;
acromion (articulates with clavicle);
•glenoid fossa or glenoid cavity (articulates with head of humerus)
what makes up the brachium
Humerus (2) – head; greater & lesser tubercles (attach scapular muscles); shaft; lateral & medial epicondyles (attach muscles of forearm and fingers)
what makes up the forearm
Ulna (2) – olecranon process ; trochlear notch (together they both form elbow
Joint)
Radius (2) – head (flat); rotates
carpus/ wrist
16 carpal bones
palm
10 metacarpal bones
fingers
28 bones
phalanges (proximal, middle, and distal in fingers; proximal and distal in thumb)
pelvic girdle
Coxae (2) –
•ilium (largest);
•ischium (bears weight when seated);
•pubis (forms joint with other pubis bone);
•pubic symphysis (cartilage between pubis bones);
•acetabulum (deep socket; for head of femur)
thigh
Femur (2) – head; greater & lesser trochanters (attach thigh and gluteal muscles); shaft; lateral & medial epicondyles (attach muscles of foreleg)
Patella (2) – kneecap; between epicondyles of femur
foreleg
Tibia (2) – medial bone; supports body weight; articulates with knee
Fibula (2) – long, slender bone; does not bear weight; does not articulate with
knee; does support ankle
tarsus/ankle
tarsal bones (talus – ankle bone; calcaneus – heel bone)
sole
10 metatarsal bones
toes
28 phalanges (proximal, middle, and distal in toes; proximal and distal in big toe)
