•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

susbtanceTypes of Fibers:

Type I collagen (fibrocartilage)type II collagen (hyaline and elastic)Elastic fibers (elastic)

Types of cellsChodroblastscondrocytes

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 cellspherical 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

Cartilage matrix

RER

N

MATRIX

Provides the rigidity, elasticity, & resilienceFIBERS

Collagenous and elastic

GROUND SUBSTANCEGlycosaminoglycans (chondroitin sulfates, keratin sulfate, hyaluronic acid)Proteoglycans: GAGs + core proteinWater

BasophilicTerritorial 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

MATRIXType II collagen (thin fibrils)Chondroitin sulfate, keratin sulfate, hyaluronic acidWaterTrritorial ,inter territorial matrix

Isogenous group

Cartilage looks like EYES

LOCATIONTracheal rings, nasal septum,larynx, articular surfaces

of joints ends of long bones,

HYALINE CARTILAGE

RubberyTranslucent,glassy appearance.Covered by perichondrium except for large articular cartilage of synovial joints.Chondrocytes in lacunea

isogenous groupsMatrix__interterritorial,territorialCollagen fibers,chondrioten sulphate

karaten sulphate,water.

Hyaline cartilage Elastic Cartilage chondrocyte

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 CARTILAGEFUNCTION

Support with flexibility

MATRIXNormal components of hyaline matrix plus ELASTIC fibers

LOCATIONExternal 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

FUNCTIONSupport with great tensile strength

LOCATIONIntervertebral disks, pubic symphysis

How many types of cartilage do you see?

A

B

C

Questions 2 and 3:

2. The three tissues shown have all of the following properties in common EXCEPT:

a. They contain capillaries.b. They contain proteoglycans.c. They can increase in size by interstitial growth.d. They can increase in size by appositional growth.

3. Which tissue is the most highly specialized to resist compression?

a. Ab. Bc. C