Cartilage Flashcards
How does cartilage receive nutrients and why?
Through diffusion of distant blood vessels because it’s a vascular and aneural
Where can we find cartilage in the human body?
Articular, costal, nasal, ears, trachea
What is cartilage?
Flexible and semi-rigid connective tissue
What makes up Cartilage?
Chondroblasts, chondrocytes and extracellular matrix
How are chondrocytes formed?
Chondroblasts surrounded by ECM. Usually stay in lacunae
What is the function of chondroblasts?
Produce ECM and fibres (collagen 2 and elastin)
What do chondroblasts derive from?
Mesenchymal cells (like osteoblasts)
What is the function of chondrocytes?
Release ECM at a very low level
What are the components of the cartilage extracellular matrix?
Collagen 2, elastin fibres, molecules. 75% water
Why is collagen significant in cartilage?
Oriented in cartilage in direction of mechanical force. Provides resistance to high tensile strength.
What provides high compressive strength to cartilage?
Water, which is bound by aggrecan molecules in ECM
What are the three main molecules found in ECM?
Glycosaminoglycans, Proteoglycans (aggrecan), Glycoproteins
What are important functions of the molecules in ECM?
Lubrication and Shock absorption (water assists this)
What are the three types of cartilage?
Hyaline, Elastic, Fibrocartilage
Where is hyaline found (6) and its appearance?
Articular, costal, nasal, trachea, bronchi, epiphysial growth plates. Glassy appearance
3 types of cartilage from strongest to weakest
Fibrocartilage, Elastic, Hyaline
Where is elastic cartilage found and it’s significance?
Ear and larynx. Has elastin fibres so returns to original shape - very flexible and resistant
Where is fibrocartilage found and its significance?
Joint capsules, intervertebral discs and tendon and ligament insertions. Dense collagen 2 bundles so very strong
What happens to cartilage with age?
Water levels decrease in body so tensile strength and shock absorption decrease
What matrix enclosed compartments do chondrocytes sit in?
Lacunae
Which vessel lays on the surface of the cartilage?
Perichondrial
How does cartilage regenerate?
It doesn’t degenerate as there is no blood supply. Once damaged, that’s it.
Describe the structure of a chondrocyte
Small nucleus, irregular shape and lipid droplets within the cell. Found arranged in lacunae
