Ch. 4: Cartilage Flashcards
Cartilage cells do not have capillary networks of their own, nutrition is accomplished by what
diffusion
what are the functions of cartilage?
support and a template for endochondral bone ossification
what are the three types of cartilage
hyaline, elastic and fibrocartilage
hyaline cartilage fiber type
collagen II
elastic fiber type
collagen II and elastic
fibrocartilage fiber type
collagen I primary, little cartilage II
does hyaline have a perichondrium
yes usually
does elastic have a perichondrium
yes
does fibrocartilage have a perichondrium
no
what is the matrix of hyaline cartilage made up of
ground substance and fibers
what is the ground substance made up of in the matrix of hyaline cartilage
aggrecans, hyaluronic acid, other proteoglycans, chondronectin
large molecules composed of proteins (forms core) and sulfated GAG’s
aggrecans
how many GAG’s per aggrecan are there
100-200
chondroitin sulfate, keratin sulfate and heparin sulfate are all examples of what
sulfated GAG’s
the fibers in the matrix of hyaline cartilage are what type
primary- collagen II
some- collagen 9, 10, 11
another name for chondrogenic cells
chondroprogenitors
appearance of chondrogenic cells
very narrow
location of chondrogenic cells
chondrogenic perichondrium
chondrogenic cells are usually derived from
usually mesenchyme cells (sometimes osteoprogenitors)
chondrogenic cells differentiate into what
chondroblasts but sometimes osteoprogenitors
function of chondrogenic cells
chondroblast source
do chondrogenic cells undergo mitosis
yes
appearance of chondroblast
oval
location of chondroblast
chondrogenic perichondrium
where are chondroblasts derived from
usually chondrogenic cells (sometimes mesenchyme cells for interstitial cartilage growth or fibroblasts for appositional cartilage growth)
what do chondroblasts differentiate into
chondrocytes
function of chondroblasts
produce all parts of matrix
do chondroblasts undergo mitosis
no
can chondroblasts be inactive for long periods of time
yes
do chondroblasts like high or low oxygen environments
low
appearance of chondrocyte
round
location of chondrocyte
interior to the perichondrium
where are chondrocytes derived from
chondroblasts
chondrocytes differentiate into what
nothing, this is the end of the cartilage cell line but they can possibly revert back to chondroblasts
chondrocytes maintain the _________ and prevent _____________
matrix; calcification
do chondrocytes produce new matrix sometimes?
yes
do chondrocytes undergo mitosis
yes
young chondrocytes can divide how many times
one or two max
what is the location of the perichondrium
peripheral to cartilage
what are the two exceptions of cartilage with no perichondrium
epiphyseal growth plates and articular cartilage (at the ends of bones)
what are the two parts of perichondrium
fibrous perichondrium and chondrogenic perichondrium
what perichondrium is the outermost layer, collagen I, primary cell type is fibroblast and is the vascular layer
fibrous perichondrium
what perichondrium is the innermost layer, thin, has chondrogenic cells and chondroblasts, collagen II, and avascular
chondrogenic perichondrium
tissue creation or the development of cartilage in the fetus is termed what
histogenesis aka chondrogenesis
interstitial cartilage growth begins with a grouping of rounded _________ cells that can be called a chondrogenic _________
mesenchymal; nodule
chondrification within the chondrogenic nodule involves what
mesenchyme cells differentiating into chondroblasts
transcription factor SOX-9 and the forces exerted in the area are factors affecting what
mesenchyme cells differentiating into chondroblasts during chondrification
chondroblasts will secrete what
matrix components
matrix concentrates sets up and does what to chondroblasts
differentiates them in to chondrocytes
chondrocytes will likely do two things: 1. secrete more matrix to turn into _______ ________ or 2. divide into _______ __________
territorial matrix; isogenic groups
what is the stopping point of cartilage development
chondrogenic perichondrium
fibrous perichondrium develops from what
surrounding vascular mesenchyme tissue
interstitial growth (a modified version) occurs in what two locations
articular cartilage and epiphyseal growth plates
the surface layer of articular cartilage is primarily densely packed with what
collagen II
in the articular cartilage, these cells are arranged in columns, may occasionally divide, and secrete some matrix for maintenance
chondrocytes
this is deep by bone and functions to seal cartilage from bone
thin crystalline mineral plate
the outer layer of the joint capsule is composed of what
fibrous dense ct
the outer layer of the joint capsule is continuous with what of adjacent bones
periosteum
another name for synovial layer
synovial membrane
this is the inner ct layer covering non-articular surfaces. It contains rich blood, lymphatic and nerve supply. It regenerates rapidly if damaged and is not considered an epithelial lining
synovial layer or synovial membrane
the synovial layer/membrane has two cell types which are what
type A synovocytes and type B synovocytes
type A synovocytes are ___________ and their function is to remove debris from joint space by phagocytosis
macrophages
type B synovocytes resemble ___________ and they secrete synovial fluid
fibroblasts
this has high concentrations of hyaluronan and lubricin
synovial fluid
_________ functions to supply nutrients and oxygen to chondrocytes while __________ functions in joint lubrication
type A synovial fluid; type B synovial fluid
what are the three types of synovial membranes
fibrous synovium, areolar synovium, and adipose synovium
this is a loose areolar ct with type A and B cells; extends into joint cavity as synovial folds and vili; occurs where there is movement
areolar synovium
this is dense irregular ct; covering tendons and ligaments
fibrous synovium
this covers intra-articular fat pads; type B cells here
adipose synovium
this occurs much slower than interstitial cartilage growth and is more common
appositional cartilage growth
appositional cartilage growth is a process that originates within where
within the perichondrium
during appositional cartilage growth what becomes active
chondrogenic cells and chondroblasts
during appositional cartilage growth new chondroblasts also develop from ________
fibroblasts in the fibrous perichondrium
during appositional cartilage growth new chondrogenic perichondrium develops from what
the previous fibrous perichondrium
during appositional cartilage growth new fibrous perichondrium develops from what
surrounding ct
what are the functions of appositional cartilage growth
enlarge existing cartilage and healing
what cartilage type has elastic fibers, larger chondrocytes, more chondrocytes, and less matrix
elastic cartilage
what is the function of elastic cartilage
to provide more flexibility
besides the few differences elastic is otherwise like ________ cartilage in basic structure and function
hyaline
the major structural features of ____________ are chondrocytes; fibrocytes and fibroblasts; collagen I and some hyaline matrix which has collagen II; no perichondrium; avascular (except in the knee menesci)
fibrocartilage
what are the two important functions of fibrocartilage
- provides strength; resist stretch/tensile forces (more collagen I)
- shock absorption; resists compressive forces (more hyaline matrix)
no appositional healing because of no perichondrium which leads to 100% scar tissue are limitations of what
fibrocartilage
in the development of fibrocartilage initially, tissue is more like ______ __________ ct with fibroblasts and fibrocytes
dense regular
in the development of fibrocartilage to resist compression and force the fibroblasts produce what
proteoglycans and GAG’s
in the development of fibrocartilage fibroblasts will change into ____________ due to the pressure from accumulating molecules
chondrocytes
in the development of fibrocartilage if there are more compressive forces then there will me more what
hyaline matrix
in the development of fibrocartilage if there is more shearing/pulling forces then there will be more what
collagen I produced by the fibroblasts
in the development of fibrocartilage some fibroblast remain which will mature into what
fibrocytes
fibrocartilage is the combination of what
dense regular ct and hyaline cartilage
as the age of cartilage increases the number of chondrocytes ________
decreases
as cartilage age increases the matrix amount ________
decreases
as cartilage age increases the calcification ________
increases (this is not an issue for elastic cartilage because of decreased number of chondrocytes) ; typically only observed with hyaline cartilage
the effects of hormones and vitamins is greatest during/on what three things
- original development of cartilage
- ossification
- epiphyseal growth plates
healing of hyaline and elastic cartilage is better or worse in children compared to adults
much better
true/false the healing of hyaline and elastic cartilage is very limited
true
during the healing of hyaline and elastic cartilage inflammation will lead to what
scar tissue formation
what is another name for osteoarthritis (OA)
Degenerative Joint Disease
osteoarthritis is pathological if it occurs when
before the age of 65 or if it occurs too severely
what are the three types of OA
- primary OA
- traumatic OA
- Inherited OA
what is the most common type of OA
peimary
primary OA is _________ related
age-related
wear and tear and muscle dysfunction are possible causes of what
primary OA
what type of OA is injury related
traumatic OA
what type of OA is from a genetic mutation to collagen II fiber that makes them weaker, could show up in the 20’s, early onset, severe and systemic
inherited OA
what is the OA cycle
cartilage decreases–> osteophytes develop–> joint irritation–> inflammation–> lose more cartilage
what functions to resist compressive forces; has much HA therefore much water; collagen II; and has no to few cells after 20’s
nucleus pulposus in the intervertebral discs
what functions to support the nucleus pulposus; composed of collagen I with some hyaline matrix; some fibrocytes and chondrocytes
annulus fibrosus= fibrocartilage in the intervertebral discs
as age increases there is _______ collagen II and ________ collagen I in the hyaline matrix
more; less
when discussing age related degenerative changes to the IVD fibrocytes make more ___________ but they are weak
proteoglycan
when discussing age related degenerative changes to the IVD chondrocytes make more _________ molecules to try to increase strength but they are still weaker
aggregant
when discussing age related degenerative changes to the IVD the nucleus pulposus is going to have ________ decrease which takes off some stress
water
what is an adhesive glycoprotein
chondronectin
what do not form aggregates; bind to other molecules; help to stabilize matrix
proteoglycans
what has bonds to many aggrecans
hyaluronic acid or hyaluronan
held between HA and the aggrecans are large amounts of what
water
