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Axial Skeleton

one of the two subdivisions of the skeleton, the bones that form the longitudinal axis of the body, the skull, vertebral column, ribs, and sternum.

Appendicular skeleton

One of the two subdivisions of the skeleton, the bones of the limbs and girdles that are attached to the axial skeleton.


Blood cell formation that occurs within the marrow cavities of certain bones.


Elongated shaft of a long bone.


the ends of the long bone, consists of a thin layer of compact bone enclosing an area filled with spongy bone.

Epiphyseal plate

a flat plate of hyaline cartilage seen in young, growing bone. Cause the lengthwise growth of the bone.

Medullary cavity

The cavity of the shaft that is a storage area for adipose (fat) tissue, also called yellow marrow.


Mature bone cells found within the matrix in tiny cavities called lacunae.


Tiny cavities in the matrix that contain osteocytes.


Concentric rings/circles made up of groups of hollow tubes of bone matrix that the lacunae are arranged in.

Central Haversion Canal

Canal that opens in the center of the osteon and contains blood vessels and nerves


Hairlike canals that connect lacunae to each other and the central canal

Volkmann's canal

Completes the communication pathway from the outside of the bone to its interior which run into the compact bone at right angles to the shaft.


process of bone formation that involves two major phases. First, hyaline cartilage model is covered with bone matrix and then the cartilage is digested away opening a medullary cavity within the newly formed bone.


bone-forming cells


giant bone-destroying cells in bones that break down bone matrix and release calcium ions into the blood.


a disease of children in which the bones fail to calcify, the bones soften and the legs bow.


a realignment of the broken bone ends (treats fractures)


blood-filled swelling when a bone breaks.

Articulation (joint)

The junction of two or more bones; an articulation.

Synarthroses/fibrous joint

an immovable joint

Amphiarthroses/cartilaginous joint

slightly movable joints. Bones united by cartilage, no joint cavity is present

Diarthroses/synovial joint

freely movable joints


the connecting fibers are longer than those of sutures; thus the joint has more "give". An immovable joint in which bones are joined by connective tissue. Between tibula and fibula.


an almost immovable joint between bones bound by cartilage.


happens when a bone is forced out of its normal position in the joint cavity.


"water on the knee" due to the inflammation of bursae or synovial membrane.


the most common form of arthritis, a chronic degenerative condition that typically affects the aged.

Rheumatoid arthritis

a chronic inflammatory disorder, it's a disorder in which the body's immune system attempts to destroy its own tissues.


When the scar tissue eventually ossifies, and the bone ends become firmly fused.

Gout (y arthritis)

a disease in which uric acid accumulates in the blood and may be deposited as needle-shaped crystals in the soft tissues of joints.


abnormal lateral curvature of the spine.


abnormal outward curvature of the thoracic spine. Humpback


Abnormal anterior curvature of the lumbar spine (sway-back condition)


a condition in which the body's bones become weak and break easily.

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