Intro to Bone and Soft Tissue Flashcards
(66 cards)
What is the purpose of cartilage?
- structural support
- protect tissues
- attachment sites
How many bones are there n the adults compared to children?
-206 in adults and 270 in children
What is the appendicular skeleton comprised of?
- pectoral girdle
- upper and lower limbs
- pelvic girdle
What is the axial skeleton comprised of?
- cranium
- vertebral column
- rib cage
What are the 5 main functionsof the skeletal system?
- movement
- support
- protection of vital organs
- calcium storage
- haematopoesis
What are the classifications of bones by shape?
- flat
- short
- sesamoid
- long
- irregular
- sutured
What type of connective tissue connects bone to bone?
-ligament
What type of one is the patella?
-sesamoid
What are osteogenic cells?
-bone stem cells
What are osteocytes?
- mature bone cells
- formed when osteoblasts become embedded in its secretions
- sense mechanical strain to direct osteoclast and osteoblast activity
What are osteoblasts?
- bone forming
- secrete osteoid
- catalyse mineralisation of osteoid
What are osteoclasts?
- bone breaking
- dissolve and resorb bone by phagocytosis
- derived from bone marrow
Where are osteocytes found?
-embedded in matrix
Where are osteoclasts found?
-bone surfaces and at sites of old, injured or unneeded bone
Where are osteogenic cells found?
-deep layers of periosteum
Where are the osteoblasts found?
-growing portions of bones, including periosteum and endosteum
What is the bone matrix made up of?
- Organic component (40%) :
- Type 1 collagen (90%)
- Ground substance (10%) - proteoglycans, glycoproteins, cytokine and growth factors - Inorganic component (60%):
- Calcium hydroxyapatite
- Osteocalcium phosphate
Tell me about immature bone.
- first bone that is produced
- laid down in a ‘woven’ matter - relatively weak
- mineralised and replaced by mature bone
Tell me about mature bone.
- mineralised woven bone
- lamellar (layer) structure - relatively strong
What are the types of mature bone?
- Cortical (stronger):
- compact, dense
- suitable for weight bearing - Cancellous:
- ‘spongy’ - honeycomb structure
- not suitable for weight-bearing
How do the structure of cortical and cancellous bone differ?
- Cancellous have trabeculae (matrix of inorganic tissue)
- Cortical has lacunae, mineralised matrix and
Tell me about the structure and organisation of compact bone.
- few spaces
- provides protection, support and resides stresses produced by weight of movement
- repeated structural units ‘Osteons’ - concentric ‘lamellae’ around a central ‘Haversian canal’
What is the Haversian Canal?
- found in compact bone
- contains blood vessels, nerves and lymphatics
What are lacunae?
- found in compact bone
- small spaces containing osteocytes
- tiny canaliculi radiate from lacunae filled with extracellular fluid