skeletal

Hyaline cartilage

The primary skeletal material in embryos.

Ossification

The process of bone formation that uses hyaline cartilage structures as models.

Bone matrix

A substance that completely covers the hyaline cartilage model by osteoblasts.

Osteoblasts

Bone building cells that lay down new bone matrix.

Medullary cavity

The hollow center created when hyaline cartilage is replaced by bone.

Epiphysial plate

The area where bones grow in length.

Osteoclasts

Giant bone-destroying cells that break down bone matrix.

Bone remodeling

The process where bones are continually remodeled in response to calcium levels and mechanical stress.

Hematoma

A localized swelling filled with blood that forms at the fracture site.

Fibrocartilage callus

The temporary tissue that forms during healing after a fracture.

Bony callus

The hard tissue that replaces the fibrocartilage callus during fracture healing.

Depressed fracture

A type of fracture where the bone is pressed inward.

Spiral fracture

A fracture that occurs when twisting forces are applied.

Communicated fracture

A fracture where the bone breaks into three or more fragments.

Tensile strength

The maximum stress a material can bear while being stretched or pulled.

Calcium salts

Minerals that deposit in bone making it hard to resist compression.

Intramembranous ossification

Formation of bone from fibrous connective tissue membranes without a cartilage stage.

Endochondral ossification

Process where most bones develop from hyaline cartilage.

Cortical bone

Another name for compact bone which is dense and forms the outer layer.

Volkmann’s canal

Canals that run perpendicular to Haversian canals, carrying blood vessels.

Lacunae

Small spaces between the lamellae that house osteocytes.

Osteon

The fundamental functional unit of compact bone.

Haversian Canal

The central channel of an osteon that contains blood vessels and nerves.

Canaliculi

Microscopic canals that connect lacunae and Haversian canals.

Lamellae

Concentric rings of calcified matrix surrounding the Haversian canal.

Osteocytes

Mature bone cells that maintain the bone matrix.

Collagen fibers

Organic components of bone that provide flexibility and tensile strength.

Mineral salts

Inorganic components such as calcium phosphate that provide rigidity to bone.

Bone growth hormones

Hormones such as growth hormones and sex hormones, that control bone growth.

Calcium ion regulation

The process that controls calcium levels in the blood affecting bone matrix formation and breakdown.

PTH (parathyroid hormone)

Hormone released when calcium levels in blood are low and activates osteoclasts.

Hypercalcemia

Condition characterized by high calcium levels in the blood prompting calcium storage in bones.

Articular cartilage

Cartilage covering the ends of long bones in adults that remain as cartilage.

Epiphyseal plates

Growth plates in long bones where new cartilage is continuously formed.