1 .
Cartilage + bone
-
derived from mesenchyme
-
cells + extracellular matrix ( ground substance hardened )
> Cartilage
-
ALWAYS avascular ✗ aneural ( no vessels + nerves )
-
few cells 95% extracell m .
,
.
-
surface covered w .
perichondrium
structure :
Chandrablasts ( in perichondrium) -
mature chondrobl .
=
chondrocytes
ce, ,g
chondrocytes
cartilage
fibers ( Coll 1. call 1.1 ,
elastin)
.
, . .
[µ
ground substance
cells arranged in in groups
in lacunas
according to the type of fibers it contains we distinguish between : -
hyalincart ( call type 11 )
. .
.
- elastic (elastin) ④
-
fibrocact ( call type 1.) ④
. .
Perichondrium :
covering ( envelope)
-
-
2 sub layers : •
fibrous layer ( dense conn .
tiss )
.
•
chondrogenic layer ( Chandrablasts)
-
vascular → nutrition + growth
-
not present in fibrocart . ✗ articular cart .
Cells :
-
embryogenic chondrogenic cells ( deriv from mesenchyme)
.
-
Chandrablasts ( inner part of
perichondrium)
-
chondrocytes ( embedded in EM , deep in cartilage)
chondrocytes
-
contains EU -
and heterochromatin
-
localised in lacunae ( small chambers)
-
many golgi rough ER and sect . vesicles -
protein production
,
-
territorial ( arroun.cl lacuna , basoph ) .
+
interterritorial matrix ( betw lacunas ) .
H C. .
Chemical com posit . of hyalin cart .
:
-
3- 5% cells -
9% proteoglycans > fibers in h . c. are not visible !
-
5% glycoproteins -
Go -
so % water
only the cell groups in lacunae
-
15% Collagen
, Growth of cartilage :
-
regeneration + growth limited in adults
-
2 ways for growth : -
Interstitial ( mitosis of chondrocytes)
appositional ( diff of Chandrablasts inside perichondrium)
-
.
Location of hyalin cart . :
-
airways ( nose , larynx
,
trachea ,
bronchi )
Functions :
-
development of bones ( fetal skeleton)
-
growth of bones lepiphyseal plates)
-
articulation between bones ( no perichondr . > avascular → synovial fluid for nutrition)
-
costal cartilages
Articular capsule > 2 sub layers : -
connective t .
-
synovial member . ( many capillaries , produces syn .
fluid )
•
synovialocytes A ( remove debris fr . fluid , like macrophages)
synovialocytes B ( fibroblastic produce hyaluronan)
•
,
EC .
Difference EC ✗ Hc :
Location :
-
auricle EC HC
-
ext .
auditory meatus
-
cartit . of larynx ( not )
all
-
fibers visible -
fibers not vis .
-
epiglottis -
more cells , no -
less cells
,
located in groups
groups
composition :
-
elastic + call . 11 .
-
flexible
-
more cells not in groups
,
-
perichondrium
-
c
Location :
pubic symphysis
-
-
inter.vertebr . discs
composition :
-
no perichondrium
-
thick call . fiber boundless
-
chondrocytes in rows / separate
Cartilage + bone
-
derived from mesenchyme
-
cells + extracellular matrix ( ground substance hardened )
> Cartilage
-
ALWAYS avascular ✗ aneural ( no vessels + nerves )
-
few cells 95% extracell m .
,
.
-
surface covered w .
perichondrium
structure :
Chandrablasts ( in perichondrium) -
mature chondrobl .
=
chondrocytes
ce, ,g
chondrocytes
cartilage
fibers ( Coll 1. call 1.1 ,
elastin)
.
, . .
[µ
ground substance
cells arranged in in groups
in lacunas
according to the type of fibers it contains we distinguish between : -
hyalincart ( call type 11 )
. .
.
- elastic (elastin) ④
-
fibrocact ( call type 1.) ④
. .
Perichondrium :
covering ( envelope)
-
-
2 sub layers : •
fibrous layer ( dense conn .
tiss )
.
•
chondrogenic layer ( Chandrablasts)
-
vascular → nutrition + growth
-
not present in fibrocart . ✗ articular cart .
Cells :
-
embryogenic chondrogenic cells ( deriv from mesenchyme)
.
-
Chandrablasts ( inner part of
perichondrium)
-
chondrocytes ( embedded in EM , deep in cartilage)
chondrocytes
-
contains EU -
and heterochromatin
-
localised in lacunae ( small chambers)
-
many golgi rough ER and sect . vesicles -
protein production
,
-
territorial ( arroun.cl lacuna , basoph ) .
+
interterritorial matrix ( betw lacunas ) .
H C. .
Chemical com posit . of hyalin cart .
:
-
3- 5% cells -
9% proteoglycans > fibers in h . c. are not visible !
-
5% glycoproteins -
Go -
so % water
only the cell groups in lacunae
-
15% Collagen
, Growth of cartilage :
-
regeneration + growth limited in adults
-
2 ways for growth : -
Interstitial ( mitosis of chondrocytes)
appositional ( diff of Chandrablasts inside perichondrium)
-
.
Location of hyalin cart . :
-
airways ( nose , larynx
,
trachea ,
bronchi )
Functions :
-
development of bones ( fetal skeleton)
-
growth of bones lepiphyseal plates)
-
articulation between bones ( no perichondr . > avascular → synovial fluid for nutrition)
-
costal cartilages
Articular capsule > 2 sub layers : -
connective t .
-
synovial member . ( many capillaries , produces syn .
fluid )
•
synovialocytes A ( remove debris fr . fluid , like macrophages)
synovialocytes B ( fibroblastic produce hyaluronan)
•
,
EC .
Difference EC ✗ Hc :
Location :
-
auricle EC HC
-
ext .
auditory meatus
-
cartit . of larynx ( not )
all
-
fibers visible -
fibers not vis .
-
epiglottis -
more cells , no -
less cells
,
located in groups
groups
composition :
-
elastic + call . 11 .
-
flexible
-
more cells not in groups
,
-
perichondrium
-
c
Location :
pubic symphysis
-
-
inter.vertebr . discs
composition :
-
no perichondrium
-
thick call . fiber boundless
-
chondrocytes in rows / separate
