Flashcards in Histology Cartilage (Lect) Deck (73)
Where can hyaline cartilage be found?
-Articular surfaces of bones
-ventral ends of ribs
-some cartilages of larynx
-tracheal and bronchial rings
What type of collagen is found in all cartilages?
type II collagen
T or F: the hyaline matrix is rigid, tough, and resistant to tearing?
What direction do the collagen fibrils run in hyaline cartilage?
Can you see the collagen in hyaline cartilage?
No, because they are small and have the same refractive index as the ground substance
What makes hyaline cartilage?
What is the consistency of the ground substance in hyaline cartilage?
firm, could be cut with a knife
What is the ground substance made of in hyaline cartilage>
proteoglycans (containing keratan sulfate)
Chrodriotin sulfate glycosaminoglycans
multiadhesive glycoproteins (Chondronectin)
What color do the territorial/capsular and interterritorial matrices appear on slides?
Territorial - dark purple
Interterritorial - light purple
What type of protein chains are found in type II collagen?
3 alpha chains
What limits the size of type II collagen in hyaline cartilage?
type IX collagen binding to their surface
What happens to the most superficial layer of type II collagen fibrils in hyaline tissue?
they align in the direction of the stress
What is the orientation of the deep layer collagen fibrils in hyaline cartilage?
Perpendicular to the underlying bone layer
What is the relative size of type II collagen fibrils to type I?
type II is much smaller
Why can the immune system not see antigens on chondrocytes?
the dense matrix molecules block large molecules like antibodies
What is the implication of the immune system not being able to see the antigens on chondrocytes?
For grafts the donors do not have to be matched
How are proteoglycan monomers linked to the hyaluronic acid tubes?
By linker proteins which bind the two together through a non-covalent link
What does GAG stand for?
Where are GAGs found?
The spindles sticking off the proteoglycan monomers that are bound to hyaluronic acid
What charge to GAG chains have?
What binds to the GAG chains?
water and counterions
What happens to GAGs in compression of hyaline cartilage?
water and counterions are forces out of the tisses and release of the force lets these things back in, tissue springs back into place as a result of repulsion of negative charges
What limits expansion of hyaline cartilage?
What are GAGs composed of?
repeating disaccharid units
What happens when proteoglycans are degraded by enzymes?
there is a loss of cartilage and joint function
What are examples of synovial joint molecules that are highly hydrated to act as lubricants?
hyalurnan, lubricin, aggrecan
What lubricant is the primary joint lubricant made by chondrocytes and synovial cells?
What type of cartilage will be found in an area where tissue is subject to compression and tension?
What are some examples of fibrocartilage in the body?
ligamentum teres of femur