BIOL125 Lecture Notes - Lecture 4: Cavitation, Microstructure, Osteoclast
BIOL week 4 LA Bone anatomy and histology
The human skeleton
- Components:
oBones in axial and appendicular skeletons
oTendons, ligaments, joints
- Functions:
oSupport/framework
oMineral and lipid storage
Yellow bone marrow
oSite of blood cell production
Red bone marrow
oProtection of soft tissue/organs
oPermitting movement via action as lever
Bone types
Anatomy of long bones
- Diaphysis
oShaft
oThick wall formed by compact bone
oMedullary cavity accommodating yellow bone
marrow
- Metaphysis
oWhere diaphysis and epiphysis meet
- Epiphysis
oWider part at each end
oCovered with compact bone (thinner than in
diaphysis)
oFilled with spongy (cancellous) bone that accommodates red bone marrow
Landmarks on bones
- Elevations and projections (eg: process and ramus)
- Openings (eg: foramen, canal, fissure, meatus, sinus)
- Depressions (sulcus and fossa; caused by blood vessels or nerves)
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- Processes
oFor attachment of tendons and ligaments (eg: crest, line, tubercle)
oFor forming joints (eg: head, neck, condyle, trochlea)
Compact and spongy bones
- Location in long bones
oSpongy bone: inside of epiphysis
oCompact bone: outside of epi-, meta-, and diaphysis
- Functions:
oSpongy (cancellous bone)
The “light-weight solution for support”
Presence of trabeculae makes it strong yet light
Contains red bone marrow blood cell production
oCompact bone
Extra tough
Protective cover of bones
Support
Resists stress
But heavy
- Compact bone:
oElementary unit in bone tissue: osteon
oTiny, lamellar columns of bone matric with a central canal
oThe central canal (called Haversian canal) accommodates blood vessels and
nerves
- Spongy bone:
oMade up by bone trabeculae (aka. Crisscross beams) trabecular bone
Compact versus spongy bone structure
- Compact bone
oOsteons are similar to the columns in the Panthenon (place)
- Spongy bone
oTrabeculae are similar to the cross struts in Eiffel Tower
Why two different types of bone?
- The combination of compact and spongy structures provides different forms of
support, strength, and protection whilst being lightweight
Histology of bone tissue
- Bone has good blood and nerve supply
oHaversian canal
- Bone is covered by periosteum
- Osteocytes = entrapped osteoblasts; far from being inactive or dead
- Osteoblasts = bone producing cell
- Osteoclast = bone eating cell
Periosteum
- A tough membrane covering bone
- Point of entry for blood and nerve supply
- Protects bone
- Assists with fracture repair
- Assists with thickening of bone (ie. Appositional growth)
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Biol week 4 la bone anatomy and histology. Components: bones in axial and appendicular skeletons, tendons, ligaments, joints. Yellow bone marrow: site of blood cell production. Red bone marrow: protection of soft tissue/organs, permitting movement via action as lever. Diaphysis: shaft, thick wall formed by compact bone, medullary cavity accommodating yellow bone marrow. Metaphysis: where diaphysis and epiphysis meet. Epiphysis: wider part at each end, covered with compact bone (thinner than in diaphysis, filled with spongy (cancellous) bone that accommodates red bone marrow. Openings (eg: foramen, canal, fissure, meatus, sinus) Depressions (sulcus and fossa; caused by blood vessels or nerves) Processes: for attachment of tendons and ligaments (eg: crest, line, tubercle, for forming joints (eg: head, neck, condyle, trochlea) Location in long bones: spongy bone: inside of epiphysis, compact bone: outside of epi-, meta-, and diaphysis. Presence of trabeculae makes it strong yet light. Contains red bone marrow blood cell production: compact bone.
