Lecture 10: Cartilage Histology Flashcards
What distinguishes one type of cartilage from another?
The Extracellular Matrix differs between types
What structures does cartilage lacks supply from?
Nerves
Blood Vessels
Lymphatics
What secretes the cartilage matrix?
Chondroblasts
Has mitotic capabilities
Where do chondrocytes come from?
Chondroblasts
What do you call a group of several chondrocytes in close proximity to each other?
An Isogenous Group
What is the structure that chondrocytes are housed in?
Lacunae: hollow space in the extracellular matrix of cartilage
What type of fibers is found in the cartilage matrix?
What is the most common
- Type II Collagen (most predominant)
- Type I Collagen
- Elastin Fibers (elastic cartilage)
Where does cartilage arise from?
Embryonic Mesenchyme
Differentiation takes places from center to outward
What is the role of perichondrium?
- Essential from growth and maintenance of cartilage
- Holds the cartilage in place
What kind of connective tissue is the perichondrium?
Dense irregular connective tissue
What types of cartilages has a perichondrium?
Which types lack it?
Perichondrium Present:
- Hyaline Cartilage
- Elastic Cartilage
Perichondrium Absent
- Hyaline Articular Cartilage
- Fibrocartilage
What are the characteristics of the fibrous (outer) layer of the perichondrium?
Produces Type 1 collagen and fibroblasts
Acts as a transitional zone
What are the characteristics of the chondrogenic (inner) layer of the perichondrium?
- Adjoins cartilage matrix
- Contains mesenchymal stem cells that have chondroblasts that can differentiate into chondroblasts
- Secretes Type II collagen
What has a vascular supply, which then allows the cartilage nearby to gain some nutrients?
The perichondrium
During periods of cartilage growth, where do new cartilage cells come from?
The perichondrium
Hyaline Cartilage
What type of collagen does it use?
Where is it found?
Type II collagen
Found in: Articular Cartilage, Larynx, Trachea, Ribs, Embryonic Developlment
What is the hyaline matrix composed of?
Territorial Matrix
Interterritorial Matrix
Gives it a glassy, opaque look
What is the epiphyseal plate made of?
Hyaline Cartilage
What is the Territorial Matrix?
What molecule is it rich in?
What molecule does it have less of?
The more intensely stained portion of cartilage around any given isogenous group.
Rich in Glucosaminoglycans [GAGs]
Less Type II Collagen
What is the Interterritorial Matrix rich in?
What does it have fewer of?
Type II Collagen
Proteoglycans
Less intense staining
Elastic Cartilage
What type of collagen does it use?
Where is it found?
Type II Collagen and Elastin
Found in: External Ear, Epiglottis, Auditory tube
Fibrocartilage Cartilage
What type of collagen does it use?
Where is it found?
Type I Collagen (Little Type II)
Found in: Intervertebral discs, pubic symphysis, and selected joint capsules
What is the purpose of Fibrocartilage?
Withstands compression and shearing forces
What is Fibrocartilage made up of in the most basic sense?
Hyaline cartilage and Dense Regular connective tissue
What is interstitial growth?
Mitotic division of preexisting chondrocytes in lacunae
Adding volume
What is appositional growth?
Chondroblast differentiation from progenitor cells in perichondrium
Where do we see type 1 collagen in cartilage?
Fibrocartilage
Outer perichondrium
How is repair cartilage different than other types?
What kinds of collagen does it contain?
What other tissue does it stimulate?
It is an intermediate between Hyaline and Fibrous Cartilage
Types 1 and 2
Facilitates bone healing - but can cause bone spurs
What lines the ends of bones where they meet inside of an articular capsule?
Articular Cartilage
(Hyaline Cartilage with no perichondrium)
