chapter 7 & 8- skeletal system Flashcards
what are the 8 bones that make up the cranium?
occipital, parietal (2), frontal, temporal (2), sphenoid, ethmoid
what are the 14 bones that make up the face?
mandible, vomer, maxillary (2), palatine (2), nasal (2), inferior nasal conchae (2), zygomatic (2), lacrimal (2)
what is the suture located between the occipital bone & parietal bones?
lambdoid
what are the bones that contain sinuses?
sphenoid, ethmoid, frontal, palatine, maxillary
at what age does the cranium reach maximum size?
5
how many thoracic vertebrae are in a human?
12
what counts as one bone in the adult human but is composed of 5 fused vertebrae?
sacrum
what is the abnormal condition of lateral curvature of the spine?
scoliosis
there is no intervertebral disc between which two vertebrae?
C1 & C2
what is the gel-like material inside the annulus fibrosis of the intervertebral disc?
nucleus pulposus
the vertebral foramen is the hole through which the what passes?
spinal cord
a lack of folic acid early in pregnancy can lead to what in the fetus, a condition where the vertebral arch fails to develop?
spina bifida
how many of the 24 ribs don’t attach at all to the sternum?
4 (floating ribs)
what are the names of the 2 bones of the antebrachial region?
ulna & radius
how many carpal bones are in one human wrist?
8
how many phalanges are in one human foot?
14
what is the big bone that spans from the hip to the knee?
femur
how many bones are in the human skeleton?
206 bones
axial skeleton
longitudinal axis with 80 bones
appendicular skeleton
-limbs with 126 bones
-consists of limbs & limb girdles to provide movement
axial skeleton functions
- support & protect organs in dorsal & ventral body cavities
- provide surface area for muscle attachment
a. adjust position of head, neck & trunk
b. perform respiratory movements
c. stabilize appendicular skeleton
skull (26 bones)
-cranium: occipital (1), parietal (2), frontal (1), temporal (2), sphenoid, ethmoid
-face: maxillary (2), palatine (2), nasal (2), vomer, inferior nasal conchae (2), zygomatic (2), lacrimal (2), mandible
-auditory ossicles (6)
-hyoid bone
sutures
skull bones interconnect at immovable joints (dense fibrous C.T.)
lambdoid suture
separates occipital bone from parietal bones
coronal suture
separates occipital bone from parietal bones
sagittal suture
separates parietal bones
squamous suture
2 of them separates temporal bone from parietal bone
sinuses
air-filled chambers inside flat bones
function of sinuses
- reduce the weight of bone
- house mucus membranes that moisten & clean incoming air
where are the sinuses located?
sphenoid, ethmoid, frontal, palatine & maxillary bones
skull development
-intramembranous ossification from many centers of ossification
-brain grows more rapidly than cranial bones
-growing skull bones held together by bands of fibrous C.T. to provide flexibility(expansion of brain, compression for birth)
-around age 5 brain stops growing in size solid sutures form between cranial bones
fontanels (soft spots)
large intersections of C.T. between bones, persist until age 5
craniostenosis
premature closure of fontanels, w/o surgery brain is crushed
microcephaly
the brain fails to enlarge, cranium remains small
vertebral column
-7 cervical vertebrae (C1-C7)
-12 thoracic vertebrae (T1-T12)
-5 lumbar vertebrae (L1-L5)
-1 sacrum (5 fused)
-1coccyx (3-5 fused)
why is the vertebral column not straight?
4 curves bring weight of body in the line with central axis
primary curves
-thoracic & sacral
-present at birth
-accommodate organs
secondary curves
-lumbar & cervical
-appear in first year
-necessary for bipedalism
*cervical = hold head up
*lumbar = standing
kyphosis
exaggerated thoracic curvature
lordosis
exaggerated lumbar curvature
scoliosis
abnormal lateral curvature
vertebral body (construction of column)
stacking
intervertebral disc (construction of column)
spacing between bodies (not C1-C2)
annulus fibrous (intervertebral discs)
fibrocartilage, outside
nucleus pulpous (intervertebral discs)
gel, inside (cushion)
shrinking height
loss of water from discs
elastic ligaments
link bodies for alignment
intervertebral foramen
holes formed by spacing from discs, allow spinal nerves to exit column
vertebral arch
bone attached to vertebral body, with the body forming vertebral forman
vertebral foramen
hole for spinal cord
vertebral canal
bony canal for spinal cord formed by stacking of vertebral foramen
spina bifida
vertebral arch fails to develop correctly at 3 weeks (fetus) & spinal cord is unprotected or even exposed, 4/1000 births show some degree (lack of folic acid)
thoracic cage
-25 bones
-1 sternum & 24 ribs
true ribs
7 pairs of separate costal cartilage to attach to sternum
false ribs
3 pairs of common shared costal cartilage to attach to sternum
floating ribs
2 pairs having no cartilage, no attachment to sternum
pectoral girdle
-4 bones
-clavicles (2) & scapula (2)
upper limbs
-60 bones
-humerus (2), radius (2), ulna (2), carpal bones (16), metacarpal (10), phalanges (28- proximal, middle, distal
-> proximal/distal for thumbs only)
carpal tunnel syndrome
-any inflammation = pressure on nerves leading to pain
-carpal arranged into rows of 4 bones
-create a U shape enclosed by the flexor retinaculum (ligament)
-all tendons, vessels & nerves of hand must pass through channel between bones & ligament (no extra space)
pelvic girdle
-2 bones
-os coxae (2)
pelvis (anatomical)
pelvic girdle (2 os coxae) + sacrum + coccyx
lower limbs
-60 bones
-femur (2), patella (2), tibia (2), fibula (2), tarsals (14), metatarsals (10), phalanges (28)
