Unit 4: Skeletal System Vocabulary

articular cartilage

dense, white, connective tissue that covers the articulating surface of bones at joints

cortical bone

dense, solid bone that covers the outer surface of all bones and is the main form of bone tissue in the long bones

hematopoiesis

process of blood cell formation

ossification

process of bone formation

osteoblasts

specialized bone cells that build new bone tissue

osteoclasts

break down bone

osteocytes

mature bone cells

trabecular bone

interior, spongy bone with a porous, honeycomb structure

axial skeleton

central, stable portion of the skeletal system, consisting of the skull, spinal column, and thoracic cage

appendicular skeleton

the bones of the body's appendages; the arms and legs

bursae

small capsules lined with synovial membranes and filled with synovial fluid; they cushion the structures they seperate

ligaments

bands composed of collagen and elastic fibers that connect bones to other bones

tendon

tissue band composed of collagen and elastic fibers that connect a muscle to a bone

tendon sheaths

double-layered synovial structures surrounding tendons subject to friction given their position close to bones; secrete synovial fluid to promote free motion of the tendons during joint movement

avulsion

a fracture caused when a tendon or ligament pulls away from its attachment to a bone, taking a small chip of bone with it

dislocation

injury that involves displacement of a bone from its joint socket

fracture

any break or disruption of continuity in a bone

osteoarthritis

degenerative disease of articular cartilage characterized by pain, swelling, range-of-motion restriction, and stiffness

osteopenia

reduced bone mass without the presence of a fracture

osteoporosis

condition in which bone mineralization and strength are so abnormally low that regular, daily activities can result in painful fractures