Quiz 2 (Modules 6-10) Flashcards
(185 cards)
Long bone parts
Diaphysis (shaft/body)
Epiphyses (ends)
Epiphyseal (growth) plate
Articular cartilage
Periosteum (surrounds bone surface)
Medullary cavity
Endosteum (lines the medullary cavity)
Sharpey’s (perforating) fibers
Thick bundles of collagen that extend from the periosteum into the bone extracellular matrix
Attaches periosteum to underlying bone
Hydroxyapatite
Crystals formed from calcium phosphate and calcium hydroxide in the bones
Calcification
Mineral salts are deposited in the framework formed by collagen in the extracellular matrix, where they crystallize and the tissue hardens Initiated by osteoblasts
Bone’s hardness depends on
crystallized inorganic mineral salts
Bone’s flexibility depends on
its collagen fibers
Tensile strength
Resistance to being stretched or pulled apart
4 types of cells present in bone tissue
Osteogenic cells
Osteoblasts
Osteocytes
Osteoclasts
Osteogenic cells
Unspecialized bone stem cells derived from mesenchyme
Only bone cells to undergo cell division
Found along the inner portion of the periosteum, in the endosteum, and in canals within bone that contain blood vessels
Osteoblasts
Bone-building cells
Synthesize and secrete collagen fibers and components for extracellular matrix of bone tissue
Initiate calcification
Turn into osteocytes
Osteocytes
Mature bone cells, main cells in bone tissue
Maintain daily metabolism, eg. exchange of nutrients and wastes with blood
Ostoclasts
“Carves out bone” - releases enzymes and acid that digest components of the extracellular bone matrix
Huge cells derived from fusion of monocytes
Concentrated in endosteum
Ruffled border on side of cell that faces bone surface
Resorption
Breakdown of bone extracellular matrix by osteoclasts
Helps regulate blood calcium level
Osteon (Haversian system)
Repeating structural units of compact bone tissue
Consists of concentric lamellae arranged around a small network of blood vessels, lymphatics, and nerves located in the central (haversian) canal
Lamellae
Circular plates of mineralized extracellular matrix
Lacunae
Located between the concentric lamellae
Small spaces which contain osteocytes
Canaliculi
Interconnecting channels that join lacunae with each other and to nearby blood vessels
Concentric vs. Interstitial lamellae
Concentric lamellae are found within osteons, interstitial lamellae are found between neighbouring osteons
Volkmann’s canals / Perforating canals
Transverse canals that allow blood vessels, lymphatic vessels, and nerves from the periosteum to penetrate the compact bone and connect with vessels and nerves of the medullary cavity, periosteum, and central canals
Function of compact bone tissue
Provides protection and support
Resists the stresses produced by weight and movement
80% of the skeleton, strongest form of bone tissue
Function of spongy bone tissue
Reduces overall weight of a bone
Support and protect bone marrow
20% of the skeleton, always covered by compact bone
4 situations in which bone formation occurs
Initial formation of bones in embryo and fetus
Growth of bones until adult sizes are reached
Remodeling of bone (replacement of old bone by new)
Repair of fractures
Where yellow bone marrow is contained
In the medullary cavity
2 methods of bone formation
Intramembranous ossification
Endochondral ossification