Cartilage

Question 1

Hyaline cartilage- Cells:

Answer 1

Chondroblasts & chondrocytes

Question 2

Hyaline cartilage-• Extracellular matrix:

Answer 2

Type II collagen fibers

GAGs- hyaluronic acid and glycoproteins

Question 3

Hyaline cartilage-Growth:

Answer 3

Appositional & interstitial growth

Question 4

Hyaline cartilage-Degeneration:

Answer 4

Does not readily degenerate

Question 5

Hyaline cartilage-Calcification

Answer 5

Calcifies – bone formation & aging

Question 6

Hyaline cartilage-Functions:

Answer 6

Supportive
• Cushioning
• Shock absorber
• Growth plate
• Model for bone formation

Question 7

Hyaline cartilage-Histology

Answer 7

•Matrix has a “glassy” appearance
because fibers and ground substance
has the same refractive index
•ECM correlates to function!
• Collagen
• Sulfated groups

Question 8

Hyaline cartilage-Locations in the body

Answer 8

• Nose (cartilaginous portion)
• Tracheal and bronchial rings
• Laryngeal cartilages
• Costal cartilages
• Articular surfaces of long bones
• Epiphyseal growth plate
• Fetal skeleton

Question 9

Appositional Growth

Answer 9

occurs from chondrogenic cells in
the perichondrium differentiating
into chondroblasts, forming a new
layer of cartilage around the
periphery of the existing cartilage

Question 10

Appositional Growth

Answer 10

occurs from chondrogenic cells in
the perichondrium differentiating
into chondroblasts, forming a new
layer of cartilage around the
periphery of the existing cartilage

Question 11

Interstitial Growth

Answer 11

occurs only in young cartilage
from cell divisions within the
cartilage

Question 12

Regeneration-Hyaline cartilage

Answer 12

regenerates very
poorly and often the
perichondrium forms
scar tissue

Question 13

Articular cartilage

Answer 13

type of Hyaline cartilage found at
articular surfaces
• does not have perichondrium

Question 14

Various regions of articular cartilage:

Answer 14

1. Tangential layer
2. Transitional layer
3. Radial layer
4. Calcified cartilage

Question 15

Elastic cartilage-Cells:

Answer 15

• Chondroblasts and chondrocytes

Question 16

Elastic cartilage-Extracellular matrix:

Answer 16

Type II collagen fibers & elastic fibers
• GAGs and glycoproteins, multi-adhessive
glycoproteins

Question 17

Elastic cartilage-Growth:

Answer 17

Appositional & interstitial growth

Question 18

Elastic cartilage-Degeneration:

Answer 18

Does not readily degenerate

Question 19

Elastic cartilage-Calcification:

Answer 19

Never calcifies

Question 20

Elastic cartilage-Function:

Answer 20

Support with flexibility

Question 21

Elastic cartilage-Locations in the body:

Answer 21

• Pinna of the ear
• External acoustic meatus
• Eustachian tube
• Epiglottis

Question 22

Elastic cartilage v hyaline cartilage

Answer 22

•Perichondrium present
•Does not degenerate as readily
as hyaline cartilage
•Is often found with hyaline
cartilage

Question 23

Fibrocartilage-Cells:

Answer 23

• Fibroblasts transform to chondrocytes

under stress

Question 24

Fibrocartilage-ECM:

Answer 24

• produced by chondrocytes and
fibroblasts
• Predominantly Type I collagen fibers
• Also contains Type II collagen fibers
• GAGs - predominantly chondroitin and
dermatan sulphates

Question 25

Fibrocartilage-Growth:

Answer 25

• Only interstitial growth (due to | absence of perichondrium)

Question 26

Fibrocartilage-Function

Answer 26

Resists deformation under stress | Support and tensile strength

Question 27

Fibrocartilage-Locations in the body

Answer 27

* Intervertebral disc (annulus fibrosis) * At the pubic symphysis * Medial & lateral menisci * Attachment of ligament to bone * Intersections of some tendons and ligaments * Articular disc

Question 28

Fibrocartilage- general

Answer 28

``` -Absence of perichondrium • Matrix contains type I (mainly) & type II collagen fibers -These fibers can be seen here with H&E and trichrome staining. ```

Question 29

Osteoarthritis

Answer 29

It is a degenerative joint disease that predominantly affects the weight bearing joints - Histopathological findings: Early- articular cartilage loses its smooth appearance (surface fibrillations, flaking) Later- progressive erosion until exposure of underlying bone (eburnation, osteophyte formation, cystic degeneration)