Cartilage

Question 1

Chondroblasts

Answer 1

Cells that secrete cartilage matrix - mitotic capabilities

Question 2

Chondrocytes

Answer 2

Mature cartilage cells in lacunae, surrounded by and maintain matrix

Question 3

Matrix of cartilage components

Answer 3

Fibers - type II collagen (mostly) Type I collagen in fibrocartilage and perichondrium - elastic fibers in elastic cartilage
Ground substance - proteoglycans
Hyaluronic acid - chondroitin suflate - keratin sulfate - aggrecan

Question 4

Hyaline cartilage characteristics

Answer 4

Surrounded by perichondrium (therefore type I collagen)
Contains type II collagen
Found in : articular cartilage (lacks perichondrium) - nasal septum, larynx, trachea, bronchi, embryonic development, ribs

Question 5

Elastic cartilage characteristics

Answer 5

Surrounded by perichondrium (therefore contains type I collagen)
Contains type II collagen
Found in external ear, epiglottis, auditory tube
Basically hyaline cartilage with elastic cartilage
Imparts stretch and recoil ability

Question 6

Fibrocartilage characterstics

Answer 6

Lacks perichondrium BUT. Still has type I collagen

Found in: IV discs, Pubic symphysis, TMJ

Question 7

Territorial vs interterritorial matrix

Answer 7

Territorial = adjacent to lacunae, high in GAG but less collagen 
Interterritorial = surrounds territorial matrix - less intensely staining, more collagen II, fewer proteoglycans

Question 8

Perichondrium characteristics

Answer 8

Interface of dense regular CT
Literally means around cartilage - but not cartilage proper
Contains vascular supply
Outer fibrous layer - produces type I collagen and elastin (transitional zone between cartilage and surrounding CT)
Inner chondrogenic layer - differentiates into chondroblasts - secretes type II collagen

Question 9

Appositional growth

Answer 9

Forms new cartilage on surface of pre-existing cartilage
Occurs within inner layer of perichondrium
Increases circumference (occurs in bones as well)

Question 10

Interstitial growth

Answer 10

Takes place within the cartilage mass - chondrocytes divide within lacunae creating isogenous groups
New chondrocytes secrete more matrix which increases mass of cartilage (secretion causes growth) limited by avascular nature

Question 11

Synovial membrane

Answer 11

Produces synovium/synovial fluid 
Lines joint cavity EXCEPT AT ARTICULAR CARTILAGE 
Lubricates articular cartilage 
Vascular CT embrace 
Regenerative properties 
Absorbs shock

Question 12

Articular capsule

Answer 12

Outer fibrous layer made of dense regular CT strengthens join
Extrinsic ligament - separate from capsule
Intrinsic ligament - part of fibrous capsule

Question 13

Articular cartilage

Answer 13

Hyaline cartilage
Reduces friction
Avascular, lacks nerve supply - nourished by synovial fluid

Question 14

Synoviocytes - make up synovial membrane - 2 types

Answer 14

Type A - macrophage like - clear articular cavity of debris - regulate inflammatory events
Type B - fibroblast like - produce synovial fluid (plasma filtrate) produce hyaluronate that combines with synovial fluid
Lubricates/nourishes the articular cartilage

Question 15

Articular cartilage made up of

Answer 15

Hyaline cartilage

Question 16

Articular cartilage layers (top to bottom0

Answer 16

Tangential (small flat chondrocytes, collagen runs parallel to surface)
Transitional (slightly larger chondrocytes, collagen runs oblique -45)
Radial (large chondrocytes - stacks oriented perpendicular to articulating surface/collagen follows)
Calcified Cartilage (rests on bone - stains dark)