Cartilage & Bone Flashcards
Describe osteoclasts
Derived from macrophages, digest bone, located between matrix and marrow cavity
Describe osteoblasts
Osteogenitor cells. Function - osteoid. Location - surface of matrix
Describe osteocytes
Derived from inactive osteoblasts, monitor protein and minerals, lacunae
Describe woven (immature) bone
Randomly arranged collagen fibres in osteoid
Describe lamellar bone
Concentric lamellae which surround Haversian canals. Parallel collagen fibres
Describe spongy (cancellous/trabecular) bone
Network of bony trabeculae filled in by bone marrow
Describe compact bone
Parallel columns (direction of stress)
What are the main functions of bone?
Supporting the body, protecting internal organs, haemopoeisis and store of inorganic substances (e.g. calcium)
Describe the process of fracture repair
Haemotoma formation - osteoclasts infiltrate and remove dead/damaged cells, fibrocartilaginous callus formation - fibroblasts - chondroblasts, bony callus formation - osteoblasts, bone remodelling - woven bone to compact bone in cortical regions
What are the layers surrounding bone?
Periosteum lines bones, endosteum lines marrow cavity
What are the most common sites for fractures?
Distal radius, neck of femur, vertebrae, lungs
What are sharpey’s filaments?
Between cartilage and bone
Describe hyaline cartilage
Blue/white. Cartilage surrounded by perichondrium. Bone ends are avascular - synovial fluid
Where can hyaline cartilage be found?
Larynx, trachea, bronchus, ear/nose, ribs, articular cartilage of joints, temporary skeleton for embryos
Describe elastic cartilage
Contains more elastic fibres than hyaline but has a similar structure otherwise
