Cartilage (Bolender)

Question 1

What are the (3) recognized types of cartilage?

Answer 1

1. Hyaline
2. Elastic
3. Fibrocartilage

Question 2

Classify the following anatomical sites according to the general type of cartilage found there:

1. Nose
2. Auricles
3. External auditory meatus
4. Auditory tube
5. Larynx
6. Epiglottis
7. Trachea
8. Bronchi
9. Intervertebral disk
10. Bone endplates
11. Pubic symphysis
12. Articular disks
13. Synovial articulations
14. Tendon insertions

Answer 2

1. H
2. E
3. E
4. E
5. H and E
6. E
7. H
8. H
9. F
10. H
11. F
12. F
13. A
14. F

Question 3

What is the chief type of collagen found in cartilage?

Answer 3

Type II collagen

Question 4

Name the types of collagens found in cartilage and describe the role of each

Answer 4

1. Type II: most abundant, provides mechanical stability for the cartilage matrix
2. Type VI: links the chondrocyte to the cartilage matrix
3. Type IX: stabilizes the type II collagen network by facilitating interaction with proteoglycans
4. Type X: associated with hypertrophic regions in cartilage, arranging fibrils into a 3D lattice suitable for calcification
5. Type XI: regulates Type II collagen fibril size

Question 5

What is aggrecan?

Answer 5

The predominant proteoglycan monomer found in the cartilage ground substance

Question 6

How is cartilage nourished?

Answer 6

by diffusion

Question 7

What is the tidemark

Answer 7

The tidemark is a feature of articular cartilage. It is a thick band of mineralized matrix separating the deepest layer (adjacent to subchondrial bone) from the three unmineralized zones above.

Question 8

Why is repair of cartilage difficult?

Answer 8

• Injury that does not cross the tidemark usually does not heal due to lack of influx of chondrogenic cells, fibrin clot, or growth factors.
• Injury extending into the bone usually does not heal completely or restore the composition and mechanical properties of the original catrilage.