6.1
- 1. Chapter 6 Section 6.1 © 2016 Pearson Education, Inc.
- 2. Why This Matters • Understanding bone anatomy and the process of bone remodeling allows you to work effectively with patients with bone diseases such as osteoporosis © 2016 Pearson Education, Inc.
- 3. 6.1 Skeletal Cartilages • The human skeleton initially consists of just cartilage, which is replaced by bone, except in areas requiring flexibility © 2016 Pearson Education, Inc.
- 4. Basic Structure, Types, and Locations • Skeletal cartilage: made of highly resilient, molded cartilage tissue that consists primarily of water – Contains no blood vessels or nerves • Perichondrium: layer of dense connective tissue surrounding cartilage like a girdle – Helps cartilage resist outward expansion – Contains blood vessels for nutrient delivery to cartilage • Cartilage is made up of chondrocytes, cells encased in small cavities (lacunae) within jelly-like extracellular matrix © 2016 Pearson Education, Inc.
- 5. Basic Structure, Types, and Locations (cont.) • Three types of cartilage: – Hyaline cartilage • Provides support, flexibility, and resilience • Most abundant type; contains collagen fibers only • Articular (joints), costal (ribs), respiratory (larynx), nasal cartilage (nose tip) – Elastic cartilage • Similar to hyaline cartilage, but contains elastic fibers • External ear and epiglottis – Fibrocartilage • Thick collagen fibers: has great tensile strength • Menisci of knee; vertebral discs © 2016 Pearson Education, Inc.
- 6. Epiglottis LarynxCartilage in external ear Cartilages in nose Trachea Cartilage in intervertebral disc Respiratory tube cartilages in neck and thorax Pubic symphysis Meniscus (padlike cartilage in knee joint) Cartilages Articular cartilage of a joint Articular cartilage of a joint Costal cartilage Thyroid cartilage Cricoid cartilage Lung Axial skeleton Appendicular skeleton Bones of skeleton Hyaline cartilages Elastic cartilages Fibrocartilages Figure 6.1 The bones and cartilages of the human skeleton. © 2016 Pearson Education, Inc.
- 7. Growth of Cartilage • Cartilage grows in two ways: – Appositional growth • Cartilage-forming cells in perichondrium secrete matrix against external face of existing cartilage – New matrix laid down on surface of cartilage – Interstitial growth • Chondrocytes within lacunae divide and secrete new matrix, expanding cartilage from within – New matrix made within cartilage © 2016 Pearson Education, Inc.
- 8. Growth of Cartilage (cont.) • Calcification of cartilage occurs during normal bone growth in youth, but can also occur in old age – Hardened cartilage is not the same as bone © 2016 Pearson Education, Inc.