Transcript CARTILAGE

Specialized connective tissue
Rigid, Elastic, Resilient –
(rebounds readily-elastic)
RESISTS COMPRESSION
AVASCULAR –
nutrients diffuse through
matrix
Functions of Cartilage Tissue
Specialized CT in which the firm
consistency of the extracellular matrix
allows the tissue to bear mechanical
stresses without permanent distortion
Supports soft tissues.
Shock-absorbing because it is resilient.
Smooth surface allows sliding against it.
Essential for growth, development of bone.
Cartilage is a type of Connective
tissue
Contents: cells,fibers and ground
susbtance
Types of Fibers:
Type I collagen (fibrocartilage)
type II collagen (hyaline and elastic)
Elastic fibers (elastic)
Types of cells
Chodroblasts
condrocytes
1.CHONDROBLAST
Progenitor (an ancestor
in the direct line)of
chondrocytes
Lines border
between
perichondrium
and matrix
Secretes type II
collagen and
other ECM
components
CHONDROCYTE
Mature cartilage
cell
spherical in shape
Nucleus_central,2
or more nucleoli
Cytoplasm__finely
granular,basophilic
2.CHONDROCYTE
Reside in a space
called the lacuna
Clear areas = Golgi
and lipid droplets
dissolve during
routine staining.
Chondrocytes in Lacunae
Chondrocytes
completely fill their
lacunae
Synthetically active,
secrete matrix
N
RER
Cartilage matrix
MATRIX
Provides the rigidity,
elasticity, & resilience
FIBERS
Collagenous and elastic
GROUND SUBSTANCE
Glycosaminoglycans
(chondroitin sulfates,
keratin sulfate, hyaluronic
acid)
Proteoglycans: GAGs +
core protein
Water
Basophilic
Territorial matrix -
PERICHONDRIUM
Dense irregularly
arranged connective
tissue (type I
collagen)
Ensheaths the
cartilage
Contains the blood
vessels that nourish
chondrocytes
It is composed of two layers
1.FIBROUS LAYER.
Outer layer
collagen and elastic fibers,large
blood vessels.
2.VASCULAR LAYER.
Cartilage forming cells
blood vessels,few collagen fibers
TYPES OF CARTILAGE
HYALINE
ELASTIC
FIBROUS
HYALINE CARTILAGE
Most widely
distributed
Bluish white color.
Strong, rubbery,
flexible tissue.
HYALINE CARTILAGE
Hyaline__glass like
appears clear
fibers__not visible under
microscope.
CHONDROCYTES
lacunae
Isogenous groups
MATRIX
Isogenous
Type II collagen (thin
group
fibrils)
Chondroitin sulfate,
keratin sulfate, hyaluronic
acid
Water
Trritorial ,inter territorial
matrix
Cartilage looks like EYES
LOCATION
Tracheal rings,
nasal septum,
larynx,
articular surfaces
of joints
ends of long
bones,
HYALINE CARTILAGE
Rubbery
Translucent,glassy appearance.
Covered by perichondrium except for large
articular cartilage of synovial joints.
Chondrocytes in lacunea
isogenous groups
Matrix__interterritorial,territorial
Collagen fibers,chondrioten sulphate
karaten sulphate,water.
Hyaline
cartilage
chondrocyte
Elastic Cartilage
ELASTIC CARTILAGE
Stucture is similar to hyaline cartilage
but has elastic fibers running in all
directions in addition to collagen.
Maintains shape, deforms but returns
to shape; flexibility of organ; strengths
and supports structures.
ELASTIC CARTILAGE
FUNCTION
Support with
flexibility
MATRIX
Normal components
of hyaline matrix
plus ELASTIC
fibers
LOCATION
External ear,
external auditory
canal, epiglottis
STAINS
Elastic fibers stain
BLACK with Weigert
stain
perichondrium
ELASTIC CARTILAGE
Elastic Cartilage
Elastic fibers (elastin)
ELASTIC CARTILAGE
Yellowish and more opaque
Chondrocyte structuer is similar
Elastic fibers
Perichondrium
Fibrocartilage
transitional between dense
connective tissue and hyaline
cartilage.
Present wherever great strength
and flexibilty is required.
Chondrocytes may lie singly or
in pairs, but most often they form
short rows between dense
bundles of collagen fibres.
collagen type I is dominant in
fibrous cartilage.
the perichondrium ABSENT
Fibrocartilage
Note the rows of chondrocytes
separated by collagen fibers.
Collagen fibers lie parallel to lines
of stress
Fibrocartilage is frequently found
in the insertion of tendons on the
epiphyseal hyaline cartilage.
FIBROCARTILAGE
FUNCTION
Support with great
tensile strength
LOCATION
Intervertebral disks,
pubic symphysis
How many types of cartilage do
you see?
C
A
Questions 2 and 3:
2. The three tissues shown have all of the following properties in
common EXCEPT:
a.
b.
c.
d.
B
They contain capillaries.
They contain proteoglycans.
They can increase in size by interstitial growth.
They can increase in size by appositional growth.
3. Which tissue is the most highly specialized to resist
compression?
a. A
b. B
c. C