AP02 - Cartilage and bones Flashcards
What are the three types of cartilage?
- Hyaline
- Elastic
- Fibrous
What are the main cell types in cartilage?
Chondrocytes
Where is the location of collagen fibre type 1?
- Bone
- Skin
- Dentin
- Cornea
- BV
- Fibrocartilage
- Tendon
Where is the location of collagen fibre type 2?
Cartilaginous tissues
Where is the location of collagen fibre type 3?
- Skin
- Ligaments
- BV
- Internal organs
Where is the location of collagen fibre type 4?
- B. memb in various tissues
Where is the location of collagen fibre type 5?
- BV wall
- Synovium
- Corneal stoma
- Tendon
- Lung
- Bone
- Cartilage
- Skeletal muscle
Describe the structure/ appearance of hyaline cartilage?
- Matrix contains moderate amount of collagen fibres
- Glassy appearance in living tissue
- Highly hydrated nature of the ground substance which consists of 3 types of GLYCOSAMINOGLYCANS
- Almost friction free surface (low coefficient of friction)
- Shock absorber
Describe the structure/ appearance of elastic cartilage?
- Matrix contains collagen fibres along with a large number of elastic fibres
- Elastic fibre netwrorks and collagen type II fibres
- Principal protein is elastin
- Springy and yellow
Describe the structure/ appearance of fibrous cartilage?
- Matrix contains limited number of cells and ground substance amidst a substantial amount of collagen fibres
- Tough and v strong
- Contains cartilage ground substance and chondrocytes
What are the three types of glycosaminoglycans found in hyaline cartilage?
- Hyaluronic acid
- Chondroitin sulphate
- Keratin sulphate
Where can hyaline cartilage be found?
- Embryonic skeleton
- Costal cartilages
- Cartilage of the nose, trachea, lining of the ends of some bones and larynx
Where can elastic cartilage be found?
Found in the internal support of the external ear and epiglottis
Where can fibrous cartilage (fibrocartilage) be found?
Found in the intervertebral discs and pubic symphysis
What is cartilage?
- Avascular form of CT
- Consists of extracellular fibres embedded in a matrix that contains cells localised in small cavities
- Amount and kind of extracellular fibres in the matrix varies depending on type of cartilage
- Nourished by diffusion
- No BV/ lymphatics or nerves
What are the functions of cartilage?
- Support soft tissues
- Provide a smooth, gliding surface for bone articulation at joints
- Enable the development and growth of long bones
What are the functions of bone?
- Supportive structures for the body
- Protectors of vital organs
- Reservoirs of calcium and phosphorus
- Levers on which muscles act to prod movement
- Containers for blood producing cells
What are the different types of bone?
- Compact (trabecular)
2. Spongy (cancellous)
What are the different classifications of bone?
- Long bones
- Short bones
- Flat bones
- Irregular bones
- Sesamoid bones
What are the characteristics of compact bone?
- Dense
What are the characteristics of spongy bone?
- Spicules of bone enclosing cavities containing blood forming cells (marrow)
Example of long bone?
- Humerus in upper limb
- Femur in lower limb
Example of short bone?
Bones of wrist and ankle
Example of irregular bone?
Bones of face
Example of flat bone?
Skull
What is the typical shape of long bones?
Tubular
What is the typical shape of short bones?
Cuboidal
What is the typical shape of irregular bones?
Bones with various shapes
What is the typical shape of flat bones?
Consist of two compact
bone plates separated by spongy bone
What is the typical shape of sesamoid bones?
Round or oval bones that develop in tendons
What are the different types of osteogenesis (bone development)?
- Intramembranous ossification
2. Endochondral ossification
What is intramembranous ossification?
- Process of bone development from fibrous membranes
- Osteoblasts differentiate directly from mesenchyme and begin secreting osteoid
- Begins as mesenchymal cells form a template of the future bone
What is endochondral ossification?
- Process of bone development from hyaline cartilage
- Pre-existing matrix of hyaline cartilage is eroded and invaded by osteoblasts, which then begin osteoid production
Which bone undergoes intramembranous ossification?
Formation of flat bones in skull, the mandible and clavicles
Which bone undergoes endochondral ossification?
All bones of body except bones involved in intramembranous ossification
