Exam #2: Cartilage Flashcards
Hyaline Cartilage
- Most common type of cartilage
- “Glassy” appearance
- Fine & delicate collagen fibrils
- Also called articular cartilage; allows free movement between articulating bones
Elastic Cartilage
- Collagen & Elastic fibers
Fibrocartilage
- Thick bundles of collagen
Where is Hyaline (articular) cartilage found?
- Where it maintains a lumen: Trachea, Nostrils, Bronchi, Larynx
- Articular surface of bone: Femur, Costochondral Joints, Sternocostal Joints
- Epiphyseal Plates
Mesenchyme
Embryonic connective tissue that has the potential to differentiate into different types of tissue
Chondroblast
- Mesenchymal cells that retract their processes & become more rounded
- Synthesize ECM
- Monitor the ECM & synthesize as needed
Chondrocyte
- A Chondroblast that has completely surrounded itself in ECM & undergoes division
- Continue to synthesize ECM (Interstitial Growth)
Isogenous Groups
Genetically uniform cells that arise from one parent cell
Perichondrium
- Membrane that surrounds cartilage
- Maintains the fitness of cartilage
- Derived from mesenchyme that has differentiated into fibroblasts
How many layers does the perichondrium have?
Two:
1) Outer
2) Inner
Outer Layer of the Perichondrium
- Fibrous layer that is protective & supportive
- Contains fibroblasts that synthesize collagen
- Also contains blood vessels, lymphatic vessels, & nerves
Inner Layer of the Perichondrium
- Cellular layer that allows for cartilage growth
- Contains chondrogenic cells that become chondroblasts & later chondrocytes
- NO blood vessels or nerves
Interstitial Growth
Growth/expansion from within cartilage
Appositional Growth
Growth from the surface of cartilage
In what two locations is cartilage not covered by perichondrium?
1) Articular surface of bone
2) Epiphyseal plates
When does interstitial growth occur?
- Embryonically & prenatally
- At the articular surface of bone
What type of cartilage growth is more common
- Appositional
- Appositional growth occurs on the surface of existing cartilage throughout life
Where are chondrogenic cells located?
- Chondrification Center
- Inner Layer of Perichondrium
What is in the matrix of hyaline cartilage?
- Type II Collagen
- Proteoglycans
- Glycoproteins
- Extracellular Fluid (which hydrate glycosaminoglycans)
Proteoglycans of Hyaline Cartilage
- Bottle brush morphology that contain a core protein & GAG (hydrated)
- Hyaluronan/ Hyaluronic Acid
What is the capsular matrix?
Matrix immediately surrounding each chondrocyte
Contents:
- Proteoglycans
- Glycoproteins
- Hyaluronan
- Type VI Collagen
Territorial Matrix
- Matrix father from the chondrocyte
- Pale blue/pink color
- Lower concentration of proteoglycans than capsular matrix
Interterritorial Matrix
- Matrix further out than the territorial matrix
- Paler blue because it contains a more dilute concentration of molecules (proteoglycans)
Properties of Hyaline Cartilage
- Avascular
- NO nerve fibers
- Matrix resists forces & compression between articular surfaces of bone
Where is elastic cartilage found?
- Auricle
- Epiglottis
- Auditory Tubes
Characteristics of Elastic Cartilage
- Larger chondrocytes than hyaline cartilage
- Elastic fibers in territorial & interterritorial matrix
- Yellow instead of blue appearance
Fibrocartilage
- Dense collagenous connective tissue
- Chondrocytes form columns squeezed between collagen bundles
Where is fibrocartilage located?
- Articular disc in TMJ
- Intervertebral Discs
- Pubic Symphysis
Osteoarthritis
- Degenerative Joint Disease
- Articular surface of bone degenerates & exposes underlying bone
- Caused by dehydration of glycosaminoglycans that happens with age
