osteoblasts
bone building cells
osteocytes
mature bone cells
osteoclasts
bone destroying cells
compact bone
hard, dense bone tissue that has little space in between components
lamellae
concentric rings made up of hollow tubes of bone matrix
central haversian canal
opening of the center of an osteon, carries blood vessels and nerves
volkmanns canals
channels lying at right angles to the central canal, connecting blood and nerve supply of the periosteum to that of the Haversian canal
lacunae
small cavities in bone that contain osteocytes
Haversian system (Osteon)
structural unit of compact bone
Spongy bone
Layer of bone tissue having many small spaces and found just inside the layer of compact bone, spaces filled with Red Bone Marrow
Endochondral ossification
process in which bone forms by replacing hyaline cartilage
Intramembranous ossification
bone develops from a fibrous membrane; example is the skull
Wolff's Law
A bone grows or remodels in response to forces or demands placed upon it
Long bones
longer than they are wide
Short bones
equal in length and width; carpal and tarsal bones
Flat bones
These bones are thin, flat, and curved. They form the ribs, breastbone, and skull.
Irregular bones
bones that are complex in shape; vertebrae, facial bones
Sesamoid bones
small bones situated within tendons; patella
Diaphysis
shaft of a long bone
Epiphysis
Broadened End of a long bone
Metaphysis
growth zone between the epiphysis and the diaphysis during development of a long bone
Periosteum
A dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles.
Endosteum
membranous lining of the hollow cavity of the bone
Medullary cavity
cavity within the shaft of the long bones filled with bone marrow
Sinus
Cavity within a bone, filled with air and lined with mucous membrane
Tubercle
Small rounded projection or process
Meatus
Tubelike passageway within a bone
Tuberosity
Large rounded projection; may be roughened
Condyle
A smooth, rounded articular process creates smooth arc of motion
Process
any bony prominence
Trochanter
Very large, blunt, irregularly shaped process found on the proximal femur
Fossa
Relatively deep pit or depression
Foramen
Round or oval opening through a bone
Axial skeleton
Portion of the skeletal system that consists of the skull, rib cage, and vertebral column
Appendicular skeleton
Bones of the limbs and limb girdles that are attached to the axial skeleton
Coronal suture
the suture between the parietal and frontal bones of the skull
Sagittal suture
between the two parietal bones
Lambdoidal suture
suture that separates parietal bones from occipital bone
Squamosal suture
between parietal bone and temporal bone on side of the skull, bordered in back by occipital bone
Fontanels
Gaps between a baby's skull that slowly close up during the first 18 months of life
Anterior fontanel
Anterior side of the skull Where the sagittal suture and coronal suture meet
Posterior fontanel
back soft spot on fetal skull between parietal and occipital bone
anterolateral fontanel (sphenoidal)
soft spot between the parietal, frontal, temporal, and sphenoid bones
posterolateral fontanel (mastoid)
soft spot between the occipital, parietal, and temporal bones
Synarthrotic joints (fibrous)
immovable joints held together by connective tissue
Amphiarthrotic joints (cartilaginous)
slightly movable joints held together by cartilage
Diarthrotic joints (synovial)
freely movable joints held together by a synovial capsule containing synovial fluid
Gliding joint
allows one bone to slide over another; found in wrist and ankles
Hinge joint
Joint between bones (as at the elbow or knee) that permits motion in only one plane
Pivot joint
Allows for rotation around the length of a bone, and only allows for rotation.
Saddle joint
type of joint found at the base of each thumb; allows grasping and rotation
Ball and socket joint
rounded head articulates with depression; shoulder and hip
Tendons
Connect muscle to bone
Ligaments
Connect bone to bone
Menisci
Pads of cartilage that lie between the articular surfaces of the bones
Bursa
fluid-filled sac that allows for easy movement of one part of a joint over another
Fracture
broken bone
Sprain
injury to a ligament
Herniated disc
protrusion of a fragmented intervertebral disc in the intervertebral foramen with potential compression of a nerve
Spina Bifida
a congenital defect that occurs during early pregnancy when the spinal canal fails to close completely around the spinal cord to protect it
Kyphosis
excessive outward curvature of the spine, causing hunching of the back.
Lordosis
abnormal anterior curvature of the lumbar spine (sway-back condition)
Scoliosis
abnormal lateral curvature of the spine
Osteoarthritis
inflammation of the bone and joint
Osteoporosis
A condition in which the body's bones become weak and break easily.
Rheumatoid arthritis
a chronic autoimmune disorder in which the joints and some organs of other body systems are attacked