59 terms

Ch. 6 - 8: Skeletal System

STUDY
PLAY
ligament
Band of regular fibrous tissue that connects bones.
epiphysis
The end of a long bone, attached to the shaft.
acetabulum
Cuplike cavity on lateral surface of the hip bone that receives the femur.
axial skeleton
The bones of the skull, vertebral column, thorax, and sternum.
axis
The second cervical vertebra; has a vertical projection called the dens around which the atlas rotates
osteoblasts
Bone-forming cells.
osteoporosis
Increased softening of the bone resulting from a gradual decrease in rate of bone formation. Adequate intake of calcium and vitamin D may help prevent this disorder.
intervertebral discs
Discs of fibrocartilage between vertebrae.
gout
The disease in which uric acid accumulates in the blood and may be deposited as needle-shaped crystals in the soft tissues of joints is called __________.
osteoclasts
Large cells that resorb or break down bone matrix. Respond to PTH thereby raising blood calcium levels.
diarthroses
Freely movable joint.
atlas
The first cervical vertebra; articulates with the occipital bone of the skull and the second cervical vertebra.
lacunae
A small space, cavity, or depression; _?_ in bone or cartilage are occupied by cells.
hematopoiesis
Blood cell formation is called __________.
periosteum
Double-layered connective tissue that covers and nourishes the bone.
diaphysis
Elongated shaft of a long bone.
rickets
The disease in children whose diets lack calcium or vitamin D, where the bones fail to calcify, is called ________.
sella turcica
depression in sphenoid bone that holds pituitary gland
chondrocytes
cartilage cells, occupy spaces called lacunae
osteons
Structural unit of compact bone consisting of a central canal, called the haversian canal, surrounded by a number of concentric rings of bony matrix called lamellae.
gomphosis
Type of fibrous joint attaching a tooth to its socket
trabeculae
the irregular latticework of thin bony plates in spongy bone tissue
paranasal sinus
any of the paired sinuses in the bones of the face adjacent to the nasal cavity that are lined with mucous membrane that is continuous with lining of the nasal cavities; maxillae, frontal, ethmoid, and sphenoid bones have paranasal sinuses.
epiphyseal plate
cartilaginous area at the ends of long bones where lengthwise growth takes place in the immature skeleton; synchondrosis
synarthroses
immovable joints
amphiarthroses
Slightly movable joints
fontanels
a soft, membrane-covered space between the bones at the front and the back of a newborn's skull
canaliculi
small canals radiating in all directions from launae, allowing for communication between osteocytes
intramembranous ossification
the process of bone formation in the flat bones of the skull and clavicle, where bone forms directly within mesenchyme arranged in sheetlike layers that resemble membranes
appendicular skeleton
bones of the limbs and limb girdles that are attached to the axial skeleton
articular cartilage
hyaline cartilage covering bone ends at movable joints
cartilaginous joints
no joint cavity; bones held together by cartilage; examples: growth plates, disks between vertebrae and the pubic symphysis
central (Haversian) canals
longitudinal canal, carrying blood vessels and nerves
compact bone
hard, dense bone tissue, usually found around the outer portion of bones, diaphysis
epiphyseal line
a remnant of the epiphyseal plate
fibrous joints
bones are joined together by dense fibrous connective tissue, lack a joint cavity
Haversian system (osteon)
central canal and all of the osteocytes it feeds
lamellae
concentric rings around the central canals of osteons
medullary cavity (yellow marrow)
cavity of long bones within the diaphysis; contains yellow marrow in adults
osteocytes
mature bone cells within lacunae organized around central canals
perforating (Sharpey's) fibers
collagen fibers running from periosteum into bone matrix
perforating (Volkmann's) canals
at right angles to the central canals; connects blood vessels and nerves of the periosteum and central canal.
red marrow
typically found within the trabecular cavities of spongy bone of long bones and in the diploe of flat bones; hematopoiesis
syndesmoses
immovable joint in which bones are joined by connective tissue; distal end of tibia and fibula.
osteogenic cell
bone stem cells, found in the membranous periosteum and endosteum, produce osteoblasts that later mature into osteocytes
menisci
flattened, shock-absorbing pads of fibrocartilage between the articulating surfaces of some joints
appositional growth
increase in bone thickness (width)
PTH
hormone that helps to increase blood calcium levels; stimulates osteoclast activity
calcitonin
hormone that helps to decrease blood calcium levels; stimulates osteoblast activity
yellow marrow
soft, fatty material found in the medullary (marrow) cavity of long bones
multiaxial joint
type of diarthrosis; a joint that allows for movements within three planes (three axes)
uniaxial joint
type of diarthrosis; joint that allows for motion within only one plane (one axis)
biaxial joint
type of diarthrosis; a joint that allows for movements within two planes (two axes)
nonaxial joint
movement tends to be linear instead of angular; carpal to carpal or tarsal to tarsal joints
synovial membrane
lining of a joint capsule that secretes synovial fluid into the joint cavity
crista galli
superior projection in the middle of the cribriform plate of the ethmoid bone; attachment of the dura of the brain
sutures
articulations in the cranial bones; immovable joints
growth hormone
hormone secreted by anterior pituitary gland that stimulates growth of bones; greatest during infancy and childhood
hyaline cartilage
most common type of cartilage; it is found on the ends of long bones, ribs, and nose; forerunner of long bones in the embryo