Cartilage Flashcards
cartilage definition
a resilient and smooth elastic tissue that covers and protects the ends of long bones at the joints and nerves
cartilage brief structure
ECM- high concentration of GAGs and proteoglycans interacting with collagen and elastic fibres
chondrocytes embedded in ECM
what surrounds the cartilage?
perichondrium
perichondrium definition
sheath of dense connective tissue that harbours the blood supply, therefore nutrients must diffuse from the perichondrium to the cartilage
how many cell types are there in cartilage?
1
what is the cell type?
chondrocytes
what is the stem cell?
chondroblasts
chondrocyte function
produce and maintain cartilagnious matrix which consists of collagen and proteoglycans
cartilage function
firm consistency that allows tissue to bear mechanical stress and prevent permanent distortion
act as shock absorbers
physical properties explained
semi rigid- water molecules bound to GAGs
three different types of cartilage
hyaline, elastic and fibrocartilage
structure of hyaline cartilage
type ii collagen embedded in hydrated gel of proteoglycans and structural glycoproteins
aggrecan- 150 side chains of chondroitin sulfate and keratin sulfate
aggrecan molecules bound to hyaluronic acid and can then bind collagen
chondronectin- multiadhesive glycoprotein that binds to GAGs and integrins- adhering chondrocytes to ECM
territorial matrix definition
ECM richer in GAGs than collagen, located around each chondrocyte
hyaline cartilage function
provides smooth, low friction surfaces in joints
structural support in respiratory tract
forms temporary skeleton of the embryo
does hyaline cartilage have a perichondrium?
yes, but only at the epiphysis and articulating surfaces of long bones
where are the chondrocytes located in hyaline cartilage?
lacunae
elastic cartilage structure
similar to hyaline, but have an abundant meshwork of elastic fibres and type II collagen
elastic cartilage location
auricle of ear, walls of external auditory canal, eustachian tubes, epiglottis and upper respiratory tract
does elastic cartilage have a perichondrium?
yes, similar in structure to hyaline cartilage perichondrium
elastic cartilage function
provides flexible shape and support of soft tissues
fibrocartilage structure
mingling of hyaline cartilage and dense connective tissue
chondrocytes occur singly and often aligned in isogenous aggregates
matrix around chondrocytes is sparse
dense bundles of type I collagen and fibroblasts adjacent to regions of hyaline cartilage
less proteoglycans
location of fibrocartilage
interveretbral discs
pubic symphysis
does fibrocartilage have a perichondrium?
no
function of fibrocartilage
provides cushioning, tensile strength and resistance to tearing and compression