MSK Cartilage Flashcards
What are the three types of cartilage?
- hyaline
- elastic
- fibrocartilage
Where is this tissue found in the human body?
- tracheal rings
- nose
- bronchi
- moveable joints (articulating surfaces)
(cartilage can bear mechanical stress without aprreciable distortion)
Chondroblasts arise from _____cells and begin secreting _____of cartilage.
- mesenchymal
- matrix material
________ envelopes cartilage and is responsible for its growth and maintenance.
Perichondrium
(fibroblasts are associated with the outer fibrous layer & chondrogenic cells are associated with the inner cellular layer)
What are the major cell types present in developing hyaline cartilage?
- mesenchyme cells
- chondroblasts
- fibroblasts
- chondrogenic cells
The outer fibrous layer of the perichondrium has which components?
- Fibroblasts
- type 1 collagen
- blood vessels
(fibroblasts differentiate from the mesenchymal cells present at the peripheral edge of the developing cartilage.)
Which cell type comprises most of the inner cellular layer of the perichondrium?
chondrogenic cells
(can differentiate into chondroblasts)
Define chondrocytes
Former chondroblasts that have completely surrounded themselves in matrix.
Define Isogenous groups.
Small clusters of chondrocytes present in the central (mature) region of cartilage.
(result of chondrocyte mitosis)
What is the circle in the photo?
Isogenous group
M= matrix, C = chondrocytes in lacunae
What do the brackets indicate?
perichondrium
M= matrix, C = chondrocytes in lacunae
What are the major matrix components of hyaline cartilage?
- collagen
- glycosaminoglycans
- chondronectin
Why does type II collagen appear as a non-fibrillar homogenous mass under light microscope?
- same refractive index as the ground substance
- fiber orientation dictated by direction of stress
- fibers are fine
What are the major glycosaminoglycans in cartilage?
- chondroitin 4-sulfate,
- chondroitin 6-sulfate
- keratan sulfate
Basophilic staining of the cartilage matrix is due to the staining of what substance?
glycosaminoglycans
Define chondronectin
glycoproteins that binds cells in the matrix
(Binds matrix components and integrins on chondroblasts and chondrocyte membranes)
What is the main difference between elastic cartilage and hyaline cartilage
they are the same, except elastic cartilage has more elsatic fibers & type II collegen in prominent.
(elastic cartilage of earlobe)
What would you stain elastic fibers with?
orcein
What is the function of elastic cartilage?
resiliency
structure the external ear, epiglottis & larynx
Describe the development of fibrocartilage.
fibroblasts secrete proteoglycans, surrounding themselves in matrix, then differentiate into chondrocytes (withou perichondrium).
Describe the characteristics of fibrocartilage.
- little cartilage matrix present
- parallel type I collagen fibers are packed together in bundles with chondrocytes wedged in rows between them.
What is the function and location of fibrocartilage?
high tensile strength (large type I collagen bundles)
pubic symphysis
tendons and ligaments
(picture of IV disc. fibroblasts have elongated nuclei; chondrocytes have dark round nuclei. Inset: chondrocytes contained within lacunae)
