skeletal system Flashcards
hyaline cartilage
forms most of the embryonic skeleton, covering ends of long bones & joint surfaces
elastic cartilage
external ear, epiglottis (flap that closes off airways when swallowing food)
fibrocartilage
pubic symphysis, intervertebral discs, menisci (piece of cartilage where two bones meet)
classifications of bones
long, short, flat, irregular
long bones
longer than wide (tubular), has a shaft and two ends (humerus, femur)
short bones
roughly cube-shaped bones of the wrist and ankle
sesamoid bones
bones that form within tendons (patella)
flat bones
thin and flattened, usually curved (sternum, ribs, most skull bones)
irregular bones
various & complex shapes (hip bones, vertebrae)
appendicular skeleton
skeleton of limbs and formed of long, short, and irregular bones
axial skeleton
skeleton of the trunk (ribs, sternum, vertebrae, pelvis, coccyx)
bone marrow production
flat bones have very little marrow production, thicker bones have more marrow production
bone markings
bone marking that is consistent is a result of a muscle, ligament, or tendon attachment, or something passing through the space (nerve, blood vessel)
tuberosity
large rounded projection
trochanter
very large, blunt, irregularly-shaped process (only in femur)
tubercle
small rounded projection
epicondyle
raised area on or superior to a condyle
spine
a sharp, slender, often pointed projection
process
any bone prominence
foramen
round or oval opening through a bone
fissure
narrow slit-like opening
fossa
shallow basin
sinus
cavity within a bone, filled with air and lined with a mucous membrane
condyle
rounded articular projection, often articulates with a corresponding fossa, smooth joint surface
facet
smooth, nearly flat articular surface
head
bony expansion carried on a narrow “neck”
head
boy expansion carried on a narrow “neck”
compact bone
outer surface of bone that appears smooth and solid to the naked eye
spongy (trabecular) bone
internally deep to compact bone layer, honeycomb network where open spaces are filled with red or yellow bone marrow, can grow quickly in response to stresses (remodel itself to provide a more stable portion of the bone internally)
diaphysis
tubular “shaft” of a bone, does not grow, long section of a bone
epiphysis
ends of a bone covered with articular cartilage, grows (adds bones at ends), found at ends of bones & joints
medullary cavity
filled with bone marrow
periosteum
well innervated and vascularized connective tissue membrane that covers the outer surface of each bone except the epiphyseal ends
covers compact bone externally
periosteum
covers spongy bone internally
endosteum
diploë
internal spongy bone of flat bones
osteon
long cylindrical structural unit parallel to the long axis of a bone that functions as a weight-bearing pillar
joints are classified on…
structure, function, shape
joints
union between two or more rigid components and classified on the material uniting the ones and degree of movement allowed
fibrous joints
bones are connected by fibrous tissue and no joint cavity is present, immovable or slightly movable, sutures (short fibers), syndesmoses (longer fibers), gomphxses (periodontal ligament)
cartilaginous joints
bones united by cartilage and no joint cavity is present, immovable or slightly movable, synchondroses (hyaline cartilage), symphyses (fibrocartilage)
synovial joints
highly movable, largest, determined by shape, plane, hinge, pivot, condyloid, saddle, ball-and-socket
synarthroses
immovable joints, axial skeleton
amphiarthroses
slightly movable joints, axial skeleton
diarthroses
freely movable joints, appendicular skeleton
plane
short gliding movements
hinge
angular movements, one axis of movement (flexion and extension)
pivot
rotational movement, non-axial
condyloid
abduction & adduction, flexion& extension, biaxial
saddle
abduction & adduction, flexion & extension, bones are more stable, biaxial
ball and socket
abduction & adduction, flexion & extension, rotation, move in all directions
ossification
bone tissue formation begins in the embryo and proceeds through childhood and adolescence as skeleton grows
membrane bones
formed directly from mesenchyme, all bones of skull
intramembranous ossification
bone coming from mesenchyme, osteoblast cells secrete bone and replace mesenchymal cells with trabecular bone and then compact bone
epiphyseal plates
growth of these plates causes bones to lengthen, maintain constant thickness
simple fracture
bone breaks cleanly but does not puncture skin
compound fracture
broken ends of the bone poke through skin
comminuted
bone fragments into 3 or more pieces, common in elderly because bones are extra brittle
compression
bone is crushed, trauma
spinal
rotational fractures, ragged break when excessive twisting forces are applied to a bone (common in sports)
epiphyseal
a bone is almost fused & bone growth is almost complete, and the epiphysis separates from the diaphysis along the epiphyseal plate
depressed
broken bone portion is pressed inward, typical of skull fracture, trauma related
greenstick
bone breaks incompletely, only one side of the shaft breaks while the other side bends, common in children
