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71 terms

The Skeletal System

Bones, cartilage, joints, and ligaments
blood cell formation
bands of fibrous tissue that bind and support bones or cartilages at joints
axial skeleton
consists of skull, vertebral column, ribs, and sternum
appendicular skeleton
contains bones of arms, legs, shoulder girdle, and pelvis
process of bone formation
projections or prominences
narrow ridge of bone
sharp thornlike projection
large, irregularly shaped projection of the femur
small, rough, rounded eminence
large, rounded elevation or protuberance
examples of processes
condyle, epicondyle, head, facet, ramus
examples of cavities
fissures, foramina/foramen, fossae, meatus, sinuses
bone tissue
compact bone
dense and smooth bone
spongy bone
bone composed of needlelike pieces with a lot of open space
long bones
mostly compact bones. Limb bones are long bones.
short bones
contain more spongy than compact bone; generally cube-shaped. Eg.'s wrist and ankle bones
flat bones
thin; usually with two layers of compact bone and a layer of spongy bone in b/w. Usually bent or curved. Skull bones and sternum
irregular bones
includes all bones that are not classified as long, short, or flat. Vertebrae of the spinal column are irreg.
bone shaft
fibrous, connective tissue membrane that covers and protects the diaphysis and that also generates new bone cells for growth and repair
medullary cavity
cavity within bone shaft that contains fatty yellow bone marrow
located at each end of the bone shaft; made of spongy bone; contains red bone marrow
articular cartilage
covers the epiphysis and protects the bone surface; provides a smooth surface to prevent friction at the joint
epiphysial plate
growth region b/w the diaphysis and the epiphysis composed of hyaline cartilage. Becomes calcified when the bone stops growing; but is visible as the epiphysial line
fluid-filled synovial membrane sacs that cushion tendons where they cross bone
cranium and facial bones
skull is divided into these two sets of bones
all of the bones in the skull except for the mandible are joined by this
bone marrow (also, spinal cord)
marrow (also, any medulla)
axial skeleton
consists of the skull, vertebral column, thorax (ribs and sternum)
frontal bone
forms the forehead, bony projections under the eyebrow, superior part of the orbits
parietal bones
(2) form most of the superior and lateral walls of the cranium
sagittal suture
place where the two parietal bones meet in the midline of the skull
coronal suture
where the two parietal bones meet the frontal bone
temporal bones
lie inferior to the parietal bones
squamous sutures
where the temporal bones meet the parietal bones
external auditory meatus
canal that leads to the eardrum and the middle ear
styloid process
sharp, needlelike projection that serves as a point of attachment for many muscles
zygomatic process
thin bridge of bone that joins with the zygomatic cheekbone
mastoid process
rough projection that serves as a point of attachment for some neck muscles
mastoid sinuses
air cavities in the mastoid process
hard, flat portion of the temporal bone
occipital bone
forms the floor and back wall of the skull
lambdoidal suture
where the occipital bone joins the parietal bones
foramen magnum
large opening at the base of the skull, allows the spinal cord to connect with the brain
occipital condyles
lay on each side of the foramen magnum, rest on the first vertebra of the vertebral column
sphenoid bone
spans the width of the skull, forming part of the floor and side of the cranium and part of the orbits of both eyes
sella turcica
Turk's saddle; small depression that holds the pituitary gland in place
sphenoid sinuses
central part of the sphenoid bone that contains many air cavities
pterygoid processes
serves as a point of attachment for muscles that control the jaw
ethmoid bone
forms the roof of the nasal cavity and part of the walls of the orbits of both eyes
crista galli
serves as the point of attachment for the dura mater
dura mater
outermost covering of the brain
number of facial bones
lower jaw
(2) upright bars of bone, connect the mandible with the temporal bones
sockets on the superior edge of the bone that contain the lower teeth
(2) fused to form the upper jawbone; all facial bones except the mandible join the maxillae
palatine processes
form the anterior part of the hard palate
palatine bones
(2) form the posterior part of the hard palate
zygomatic bones
(2) the cheekbones; serve as part of the lateral walls of the orbits
lacrimal bones
(2) form the medial walls of each orbit; has a groove for tears
nasal bones
(2) form the bridge of the nose
vomer bone
(1) lies in the median line of the nasal cavity, forms most of the nasal septum
inferior conchae
(2) project from the lateral walls of the nasal cavity; extensions of the ethmoid bone
number of cranial bones