Ch. 7.4 Skeletal System Key Terms
The part of the skeleton that includes the limbs (arms and legs) and the bones that attach them to the axial skeleton (shoulder and pelvic girdles).
Diaphysis
The shaft or central, elongated portion of a long bone.
Fontanels
The "soft spots" on an infant's skull, where the fibrous membranes connecting the cranial bones have not yet ossified (turned to bone).
Medullary canal
The central cavity within the diaphysis (shaft) of long bones, where bone marrow (primarily yellow marrow) is stored.
Periosteum
A dense, tough layer of vascular connective tissue that envelops the outside of a bone, except at the surfaces of the joints.
Axial Skeleton
The part of the skeleton that forms the central axis of the body, including the skull, vertebral column (spine), and thoracic cage (ribs and sternum).
Endosteum
A thin membrane that lines the inner surface of the bony tissue, especially the medullary canal.
Foramina
Openings, holes, or passages in a bone, typically for the passage of blood vessels and nerves.
Metacarpals
The five long bones that form the palm of the hand, connecting the carpals to the phalanges.
Phalanges
The bones of the fingers and toes.
Carpals
8 small bones that make up the wrist
Epiphysis
The ends of a long bone, which are typically wider than the diaphysis and are covered with articular cartilage.
Humerus
The long bone of the upper arm, extending from the shoulder to the elbow.
Metatarsals
The five long bones that form the main part of the foot, connecting the tarsals to the phalanges.
Radius
The lateral (thumb-side) bone of the forearm, lying parallel to the ulna.
Clavicles
The collarbones; two long, thin bones that connect the sternum (breastbone) to the scapulae (shoulder blades).
Femur
The thigh bone, the longest, heaviest, and strongest bone in the human body.
Joints
these are the points where two or more bones meet, allowing for movement (or providing structural stability).
Os Coxae
The hip bone or coxal bone, formed by the fusion of the ilium, ischium, and pubis.
Red marrow
Soft, specialized tissue found in the spongy bone of the epiphyses (ends) of long bones and in flat bones; it is the primary site of hematopoiesis (blood cell formation).
Cranium
The part of the skull that encloses and protects the brain.
Fibula
The long, thin, lateral bone of the lower leg, parallel to the tibia.
Ligaments
Strong bands of fibrous connective tissue that connect bone to bone across a joint.
The kneecap, a small, flat, triangular bone located at the front of the knee joint.
Ribs
The long, curved bones that form the rib cage, protecting the organs of the chest.