midterm anatomy Haversian system (osteon)/ compact bone

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What is the Haversian system/osteon?***

structural functional unit of compact bone

Haversian Canal (Central Canal)

A hollow channel in the middle of the unit that holds small blood vessels, capillaries, lymph vessels, and nerve fibers to supply nourishment

concentric Lamellae

surround a central (haversian) canal running longitudinally

Lacunae

Tiny, fluid-filled spaces located between the lamellae that contain osteocytes

Osteocytes

Mature bone cells that were once osteoblasts and are housed safely inside the lacunae

Canaliculi

canals that connect lacunae, allowing osteocytes to share nutrients and remove wastes

Volkmann’s Canals:

transverse channels that transmit blood vessels from the outer surface into the bone tissue

Haversian system (osteon) function

• Nourishment: Delivers oxygen and blood-borne nutrients to deep bone cells (osteocytes) that cannot get food through the hard outer bone matrix.

• Strength: Arranges mineral deposits in a tight, cylindrical pattern to handle physical stress and weight.

• Repair: Serves as a dynamic path for internal bone remodeling, allowing old bone to break down and new bone to form over time

what is compact bone?

dense outer shell of osseous tissue that covers surface of all bones

collagen fibers what do they do

Collagen fibers make the rings.

Wolfs law

bone is formed where its needed, thicker and bigger where mechanical stresses are.