Cartilage Flashcards
Where does cartilage develop from?
Mesenchyme
Characteristics of cartilage
Consists of cells, tissue fibers and ground substance
Nonvascular (diffusion)
Strong, rigid and flexible
What cells are within cartilage?
Chondrogenic –> chondroblasts and chondrocytes
What are the 3 types of cartilage?
Elastic, hyaline and fibrocartilage
What is the function of cartilage?
Forms the supporting framework of organs
Lines the surface of articulating bones
Forms the template for growth and development of long bones
What is the ECM of cartilage composed of?
Glycoanimoglycans (GAGs) and proteoglycans
Collagen and elastic fibers
This makes the ECM firm and resistant to mechanical forces
Hyaline Cartilage
Most common and the skeletal model for most bones
Type II collagen fibers that cannot be seen
Covered by perichondrium
Found in trachea
Hyaline cartilage in adults
In adults it’s replaced by bone except for articular surfaces, costal cartilage, larynx, nose, trachea and bronchi
Does not calcify under normal conditions in the adult
Perichondrium
Covers the surface of hyaline and elastic cartilage
Dense CT composed of fibroblasts and type I collagen fibers
Contains blood vessels
Outer fibrous layer, inner cellular layer (chondrogenic)
What does each chondroblast give rise to?
A group of isogenous chondrocytes all derived from one chondroblast
Where do chondrocytes lie?
Cell nests in lacuna
Why are collagen II fibers invisible in cartilage?
Because of similarity in refractive index with the ground substance
Why is ground substance basophilic?
Because of chondroitin sulfate content
What happens to mesenchymal stem cells in cartilage?
reach the inner perichondrial layer differentiate into chondroblasts
Chondroblasts
Mature and secrete cartilaginous matrix and get trapped in it and become chondrocytes