Cartilage Histology

Question 1

Define cartilage

Answer 1

A semi-rigid tissue comprised of cells and ECM

Question 2

What does the ECM of cartilage contain and why is this important

Answer 2

Collagen and elastic fibers

These are crucial to the survival of chondrocytes

Question 3

Are there nerves or lymphs or arteries in cartilage

Answer 3

No

Question 4

What are the two cell types of cartilage and what is their relationship

Answer 4

Chondroblasts and chondrocytes

Chondroblasts are immature cells that are mitoticly active. They secrete cartilage matrix when told to do so which makes chondrocytes

Chondrocytes are mature cartilage cells which make their own lacunae (a physical space within ECM)

Question 5

What type of collagen is most dominant in the ECM of cartilage? Where can the two other types be found

Answer 5

Type II is most dominant

Type I is present in firbocartilage and outer perichondirum

Elastin fibers are present in elastic cartilage

Question 6

What is the ground substance of cartilage composed of

Answer 6

Proteoglycans

Question 7

What are the three types of cartilage

Answer 7

Hylaine
Elastic
Fibrocartilage

Question 8

Define hyaline cartilage

Surrounded by?
Contains what collagen?
Location in body?

Answer 8

Surrounded by perichondrium

Contains type II collagen

Located in articular cartilage, larynx, trachea, ribs

Question 9

Define elastic cartilage

Surrounded by?
Contains what collagen?
Location in body?

Answer 9

Surrounded by perichondrium

Contains type II collagen

Located in external ear, epiglottis auditory tube

Question 10

Define fibrocartilage

Surrounded by?
Contains what collagen?
Location in body?

Answer 10

Lacks a perichondrium

Contains type I collagen

Located in IVD, pubic symphsis, TMJ

Question 11

What are the two types of cartilage matrix

Answer 11

Territorial matrix

Interterritorial matrix

Question 12

What are isogenous groups

Answer 12

Groups of 2 - 3 chondrocytes in Hyaline cartilage

Question 13

Define territorial matrix

Answer 13

Contains moderate staining

Consists mainly of type II collagen randomly arranged

High in GAGs

Question 14

Define interterritorial matrix

Answer 14

Surrounds the territorial matrix

Less intense staining

Contains more collagen type II with fewer proteoglycans

Question 15

Which cartilage ECM has more proteoglycans

Answer 15

Territorial matrix

Question 16

What cartilage is used in bone development

Answer 16

Hyaline cartilage

Question 17

Define the perichondrium

Answer 17

Comprised of dense irregular CT

Contains vascular supply for cartilage

Only has hyaline and elastic cartilage

Is the source of new cartilage cells

Contains two layers

Question 18

What is the function of the fibrous layer of the perichondrium

Answer 18

This is the outer layer that produces Type I collagen and elastin

Is also the transitional zone between cartilage and the surrounding CT

Question 19

What is the function of the chondrogenic layer of the perichondrium

Answer 19

Inner layer that differentiates into chrondroblasts and then into chondrocytes in the fibrous layer

Secretes type II collagen

Question 20

Define elastic cartilage

Answer 20

Contains hylaine cartilage plus elastic fibers within the ECM

Allows for recoil and rebound

Retains shape after deformation

Question 21

Define fibrocartilage

Answer 21

Combination of hyaline cartilage and dense regular CT

Contains type I and II collagen

Chondrocytes are aligned in rows and isogenous groups

Withstands compression and shearing forces

Question 22

How are fibers oriented in firbocartilage

Answer 22

In the direction of functional stress

Question 23

Define appositional growth within chondrogenesis

Answer 23

Formation of new cartilage on surface of existing cartilage

Achieved through inner layer of perichondrium

Will come back

Question 24

Define interstitial growth

Answer 24

Takes place within a cartilage mass

Chondorcytes divide within lacunae, creating new isogenous groups

More matrix is secreted

More chondrocytes formed from existing chondrocytes

Question 25

Appositional growth overall definition

Answer 25

Growth of undifferentiated cells of the perichondrium

Question 26

Interstitial growth overall definition

Answer 26

New cells added from chondrocytes within isogneous group, this increases the overall cell size

Question 27

What makes up a synovial joint

Answer 27

An articular capsule, articular cartilage, and synovial membrane

Question 28

Define articular capsule

Answer 28

Outer fibrous layer of synovial joint made up of dense regular CT

Question 29

Define articular cartilage

Answer 29

Made up of hyaline cartilage Reduces friction with no vasculature Nourished by synovial fluid Has distinct layering Collagen fibers run perpendicular to the tissue surface and bend gradually to form an arc

Question 30

Define the synovial membrane

Answer 30

Lines joint cavity, except articular cartilage Lubricates articular cartilage Produces synovial fluid Absorbs shock

Question 31

What are the four layers of articular cartilage

Answer 31

Superficial zone Intermediate zone Deep zone Calcified zone

Question 32

Define the superficial zone of articular cartilage

Answer 32

Chondrocytes are small and flattened parallel to the surface Collagen fibers are parallel here

Question 33

Define intermediate zone of articular cartilage

Answer 33

Chondrocytes slightly larger and round Occurs both alone and in isogenous groups Collagen fibers run oblique here

Question 34

Define deep zone of articular cartilage

Answer 34

Large chondrocytes form radial columns Stacks are oriented perpendicular to the articulating surface Collagen fibers follow orientation of chondrocyte columns

Question 35

Define calcified zone of articular cartilage

Answer 35

Rests on the underlying cortex of the bone Matrix of the calcified cartilage layer stains darker here