Bone and Cartilage Flashcards
Cartilage Tissue function and characteristics
function: support with the ability to withstand mechanical stress without permanent distortion.
- avascular;
- lacks nerves and lymphatics
- poor healing
How does Cartilage tissue get its nourishment?
diffusion from capillaries and tissue fluid.
What is the function of Bone
Protection, support, blood formation and attachment site for skeletal muscle
What is the difference between perichondrium and periosteum?
Both are vascular and innervated, contain fibroblasts, collagen and ground substance
Periosteum covers the external surface of bone. contains osteogenic cells
Perichondrium: covering all cartilage except articular cartilage and fibrocartilage. contain chondrogenic cells. fibroblasts are rich in type 1 collagen
chondroblast
sphindle shaped
-synthesize and deposit cartliage
Function of chondrocyte
-completely surrounded by extracellular matrix- -can produce extracellualr matrix and metalloproteinase
Metalloproteinase
An enzyme that degrades cartilage material , allowing cells to reposition themselves
Isogenous groups and what do the contribute to
groups of 2-5 chondrocytes that were derived from a single progenitor cell
- contribute to interstitial growth
Lacunae
cavities in the matrix that contain individual chondrocytes
Pericellular matrix and how does it stain
(capsule)
-located immediately around the chondrocytes, dark basophilic stain
Differentiate between territorial and interterritorial matrix.
Interterritorial matrix is poorly stained; more acidophilic, more collagen fibers than terriorial matrix. between isogenous groups
Territorial matrix stains basophilic
- surround isogenous group
- more ground substance than capsule
- metachromatic-chondroitin sulfate
Cartilage canals
> 3mm, may have blood vessels carrying blood somewhere else
Two forms of cartilage growth: Appositional and Interstitial. Identify the similarities and differences.
Appositional growth (at surface): proliferation of chondrogenic cells into chondroblasts
Interstitial growth (within: cell division of preexisting chondrocytes within cartilage. Occurs during early phases of cartilage formation, increase tissue mass by expanding cartilage within.
Similarities: synthesis of matrix contributes to cartilage growth
Developing cartilage
proliferation within
-rationale for isogenous groups
Mature cartilage
made of isogenous groups- (2-5) cells per group (chondrocytes)
What determines different cartilage types?
composition of the matrix
Interstitial material of all cartilage
-very hydrated (60-80%) by weight
-collagenous fibers (type 2 collagen)
-elastic fibers
-ground substance :
chondroitin, keratan sulfate, hyaluronic acid
In H and E stain. What color does chondroitin stain? What color does collagen basic protein stain?
basophilic, acidophillic
What is fibrocartilage characterized by?
A few chondrocytes arranged in columns or rows- acts as transition tissue between hyaline cartilage, bone and fibrous tissue.
Endosteum
covers inner of bone- represents boundary between bone matrix and marrow cavities
Lacuna
Space in bone matrix around an osteocyte
Cannaliculi
connect lacuna to lacuna, will have capillaries and nerve fibers will send out projections that communicate with other osteocytes
Sharpey’s fibers
collagen fibers from periosteum, continous with collagen fibers of bone-found at bone/tendon or ligament junction. insert oblique or perpendicular to the access of the bone. Insertions are very strong.
What are the differences in structure of hyaline, elastic and fibrocartilage?
Hyaline: Type 2 collagen,transparent in thin sections
Elastic: matrix fibers are collagenous and elastic. type 2 collagen
fibrocartilage: LACKs Perichondrium, so growth depends on interstitial growth. characterized by few chondrocytes arranged in columns and rows
What is does each type of cartilage function?
hyaline: forms embryonic skeleton and provides longitudinal growth of bone.
elastic: flexible support
fibrocartilage: acts as a transition tissue between hyaline cartlage, bone and fibrous tissue. function: firm support with tensile strength.
Differentiated and specialized for supporting weight- dynamic tissue continuously being reorganized- highly vascular contrary to cartilage refers to what type of tissue
osseous