Cartilage Lecture

Question 1

What is a functional unit?

Answer 1

The matrix

Question 2

What are bone and cartilage considered?

Answer 2

CT

Question 3

C and B serve as Ion reservoir

Answer 3

Calcium (99%),
Phosphorus (85%)

Question 4

Bones are derived from…

Answer 4

Mesenchyme (embryonic CT)

Question 5

Face bones are derived from…

Answer 5

Ectomesenchyme (neural crest deriv)

Question 6

What is the major mineral that forms bone?

Answer 6

Hydroxyapatite

Question 7

What type of series does cartilage enamel form of biomineralized tissues

Answer 7

continuous series

Question 8

What controls the degree of mineralization of tissues?

Answer 8

SCPP genes

Question 9

What is a major fiber in cartilage?

Answer 9

Collagen

Question 10

What are the 3 components of cartilage?

Answer 10

• Cells (chondrocytes)
• Fibers (collagen)
• Ground substances (proteoglycans)

Question 11

Is connective tissue avascular and anervous?

Answer 11

-Yes (no pain!)
-Surrounded bydense connective tissue called perichondrium

Question 12

Physical characteristics of cartilage

Answer 12

Semirigid
pliable
gelatinous
not compressible
smooth

Question 13

ID: Perichondrium, Chondroblast, Chondrocyte

Answer 13

Question 14

Where do chondrocytes live?

Answer 14

In lecuna

Question 15

ID: matrix, chondrocyte, lecuna

Answer 15

Question 16

Hyaline cartilage images

Answer 16

Question 17

Hyaline cartilage functions

Answer 17

• most dominant type of cartilage
• provides still but flexible support; can break
• reduces friction in bony areas

Question 18

Hyaline cartilage locations

Answer 18

• ribs
• joints
• larynx, trachea, bronchi
• nasal septum

Question 19

What type of collagen in hyaline cartilage

Answer 19

Type 2

Question 20

Elastic cartilage images

Answer 20

Question 21

Elastic cartilage functions

Answer 21

• provides support, but tolerates distortion without damage and returns to original shape; does not break

Question 22

Elastic cartilage locations

Answer 22

• external ear
• epiglottis
• auditory tube

Question 23

Elastic cartilage type of collagen

Answer 23

Type 2

Question 24

Fibrous cartilage images

Answer 24

herringbone

Question 25

Fibrous cartilage functions

Answer 25

- resists compression to twist and force - prevents bone-to-bone contact - limits relative movements

Question 26

Fibrous cartilage locations

Answer 26

- knee/meniscus - pubic bones/pelvis - intervertebral discs

Question 27

Fibrous cartilage type of collagen

Answer 27

Types 1+2

Question 28

Which collagen type anchors cells to matrix?

Answer 28

Collagen VI

Question 29

Which GAGS are specifically associated with cartilage?

Answer 29

- hyaluronan - chondroitin sulfate - keratin sulfate

Question 30

What is an aggrecan aggregate?

Answer 30

Aggrecan is a large proteoglycan with chondroitin sulfate and keratan sulfate chains that endow articular cartilage with its ability to withstand compressive loads

Question 31

Aggrecan aggregate charge

Answer 31

negatively charged

Question 32

What are the 2 most important multi-adhesive proteins for cartilage problems?

Answer 32

- anchorin - fibronectin

Question 33

What is the function of multiadhesive proteins?

Answer 33

- Influence interactions of chondrocyte and molecules in the ECM - Can be used as clinical markers of cartilage degeneration in articular cartilage of joints

Question 34

Do chondrocytes fill the lacunae?

Answer 34

- Young ones do, old ones do not

Question 35

Chondrocyte image with young and old chondrocytes

Answer 35

*White ring = old

Question 36

Chondrocytes – Isogenous Groups

Answer 36

- Isogenous groups are a group (up to 8) chondrocytes with a single origin

Question 37

Capsular matrix

Answer 37

- darker - type 6 collagen - directly in contact w chondrocytes

Question 38

Territorial matrix

Answer 38

- lighter - secreted by isogenous group - area around cell

Question 39

Matrix components ID

Answer 39

Question 40

What type of collagen in perichondrium?

Answer 40

T1

Question 41

Define perichondrium

Answer 41

- regular, white, fibrous CT that surrounds cartilage

Question 42

What type of cartilage has perichondrium?

Answer 42

HYALINE ONLY

Question 43

2 portions of perichondrium

Answer 43

- fibrous (outside) - cellular (inside)

Question 44

Perichondrium ID

Answer 44

Question 45

What type of capsule do joints have?

Answer 45

synovial capsule with fluid (2 layers of cartilage working against each other)

Question 46

T/F: articular cartilage is a type of hyaline cartilage?

Answer 46

TRUE

Question 47

What is a tide mark the boundary for?

Answer 47

Boundary between calcified and uncalcified cartilage

Question 48

articular cartilage layers

Answer 48

- tangential - transitional - radial - calcified (transitional tissue, attached cartilage to bone) - bone

Question 49

articular cartilage layers ID

Answer 49

Question 50

Type 2 collagen orientation

Answer 50

- parallel to surface - perpendicular to bone

Question 51

Why is osteoarthritis painful?

Answer 51

bone to bone contact (bone is innervated)

Question 52

Normal vs OA Cartilage

Answer 52

Question 53

How many ways to grow cartilage?

Answer 53

2; interstitial and appositional

Question 54

Interstitial growth

Answer 54

- Slow - Resisted by matrix - Ex: isogenous group division (made by mitosis)

Question 55

Apositional growth

Answer 55

- Faster - Not limited by matrix - Comes from perichondrium - Involves the addition of new cells to the surface of the tissue

Question 56

chondroblast vs chondrocyte

Answer 56

blast: a cell that secretes the matrix of bone, but is not fully enclosed in matrix cyte: cell inside of tissue, embedded in matrix *chondroblasts eventually form chondrocytes via chondrogenesis

Question 57

T/F: there is perichondrium in joints?

Answer 57

FALSE

Question 58

Apositional growth diagram

Answer 58

Question 59

ID type of cartilage

Answer 59

Hyaline

Question 60

ID

Answer 60

Elastic

Question 61

ID

Answer 61

Elastic

Question 62

ID

Answer 62

Elastic

Question 63

ID

Answer 63

Elastic

Question 64

ID

Answer 64

Elastic

Question 65

T/F: there is perichondrium in fibrocartilage?

Answer 65

FALSE

Question 66

ID

Answer 66

Fibrocartilage

Question 67

ID

Answer 67

Fibrocartilage

Question 68

Chondrogenesis steps

Answer 68

- condensation - proliferation and differentiation - differentiation and maturation - terminal differentiation

Question 69

ID

Answer 69

Fibrocartilage

Question 70

Chondrogenesis phases

Answer 70

- MSCs - Chondroprogenitors - Chondroblasts - Chondrocytes - Hypertrophic chondrocytes

Question 71

Appositional growth image

Answer 71

Question 72

Interstitial growth image

Answer 72

Question 73

Repair of cartilage

Answer 73

- limited due to avascularity of matrix (must be through diffusion) - repair is easier if perichondrium is involved and present - damaged cartilage is usually replaced by dense connective tissue - if blood vessels enter the wound, bone grows instead of cartilage (pain follows) - Hyaline cartilage calcifies due to age and is replaced by bone