Cartilage Tissue Flashcards

1
Q

What 4 types of tissue are focused on in histology?

A

Epithelium
Muscle
Connective
Nervous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the characteristics of cartilage in general?

A

Semirigid supporting tissue - strong but slightly flexible
Withstands compressive forces incurred by locomotion and weight bearing
Avascular - no lymphatics or blood vessels
Aneural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many types of cartilage are there?

A

Three

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the location of hyaline cartilage?

A

Nose, articular surfaces, costal cartilage, respiratory system
• translucent blue-white appearance in fresh samples
Fetal skeleton (to be replaced eventually by bone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the matrix composition of hyaline cartilage?

A

Type II collagen

Chondroitan sulfate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is type II collagen?

A

Organizes and anchors ground substance

Only found in cartilage and thinner than type I cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is chondroitan sulfate function?

A

Binds water and resists compression
Provides a shock absorbing quality to cartilage matrix
This matrix is non-fibrous in appearance with routine light microscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are chondrocytes?

A

Relatively mature cells located throughout matrix

• relatively large round cells living in lacuna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the lacuna?

A

Spaces in the matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In what configurations can chondrocytes be located?

A

Maybe located individually or within isogenous groups (clusters)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function of chondrocytes?

A

responsible for some growth and most maintenance of cartilage matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are chondroblasts?

A

Relatively immature cells located at the periphery of the matrix
Relatively small ovoid cells at the edge of the cartilage matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the function of chondroblasts?

A

Contribute to the growth and repair of cartilage matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the perichondrium?

A

Transition tissue at the periphery of the cartilage

Contains the vasculature and provides for growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the two components of perichondrium?

A

Chondrogenic perichondrium

Fibrous perichondrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does Chondrogenic perichondrium contain?

A

inner layer containing chondroblasts and type II collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does Fibrous perichondrium contain?

A

outer layer containing fibroblasts and type I collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Is the perichondrium present in articular cartilage?

A

no it is absent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where is elastic cartilage found?

A

external ear, auditory tube, epiglottis, parts of larynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is elastic cartilage made of?

A

Type II collagen, chondroitan sulfate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the function of elastic fibers in elastic cartilage?

A

Provide greater elasticity than hyaline cartilage exhibits
Appear as short, sinusoidal lines in matrix (usually densely packed)
Fresh samples are more yellowish than hyaline cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Are chondrocytes, chondroblasts and a perichondrium present in elastic cartilage?

A

Yes the only difference is elastic fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where is fibrocartilage located?

A

intervertebral disks, pubic symphisis, articular disks, menisci of knee

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the function of fibrocartilage?

A

present where tough support or tensile strength is required

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what type of collagen does fibrocartilage contain?

A

Contains both type I and type II collagen

This matrix has a uniformly fibrous appearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What type of cartilage is the strongest?

A

Fibrocartilage due to the type I collagen present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Are condrocytes present in fibrocartilage?

A

Yes, Chondrocytes tend to be grouped and separated by bundles of collagen fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Is there a true perichondrium in fibrocartilage?

A

no true perichondrium is present

type I collagen blends with the type I collagen of bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what are the two types of cartilage growth mechanisms?

A

Intersititial growth

Appositional growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is interstitional growth?

A

Growth from inside out
Process:
1) chondrocytes divide inside their lacunae
2) they separate by secreting matrix between themselves
3) this method of growth works well early on but slows as cartilage matures
4) isogenous groups are more prevalent as interstitial growth becomes less effective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is appositional growth?

A

Depends on the presence of a functional perichondrium
the process:
1) perichondrial chondroblasts secrete new matrix on the existing cartilage
2) perichondrium pushes outward as a result
3) as chondroblasts lag behind the outward moving perichondrium they
become chondrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Does growth mechanisms occur simultaneously?

A

yes both can occur simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Where does endochondral ossification occur?

A

in all bones except for flat bones and facial bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is endochondral ossification?

A

Hyaline cartilage replacement in the development of most long bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What are mesenchymal cells?

A

Essentially stem cells that exist in the fetal areas where these bones will form.
These are multipotential cells capable of becoming a variety of cell types

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

what do some fetal mesenchymal cells initially differentiate into to start the endochrondal ossification process?

A

Chondrogenic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What do chondrogenic cells divide into?

A

chondroblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what do chondroblasts initially produce ?

A

a hyaline cartilage model of bone
Chondroblasts have a peripheral perichondrium (both chondroblasts and mesenchymal cells)
will grow in size by both intersitial and appositional growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

where do blood vessels start developing?

A

In the surrounding mesenchyme at the same time as hyaline cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what changes do the developing vasculature cause to the periphery of the cartilage model?

A

Cartilage cells start dying and are replaced by bone cells

Results in a conversion of the peripheral cartilage matrix into bone matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

do blood vessels eventually grow through the perichondrium? if yes, where?

A

yes, they grow through the perichondrium at about the mid-diaphysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What creates the primary ossification center in the diaphysis?

A

when blood vessels grow through the perichondrium at about mid-diaphysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What does the blood vessel that succeeds in the diaphysis of the bone eventually turn into?

A

The nutrient artery for the bone

44
Q

What cells are brought into the primary ossification center to start developing bone cells?

A

mesenchymal cells

45
Q

in the vascular environment, what do mesenchymal cells differentiate into?

A

Osteogenic cells

46
Q

What do osteogenic cells divide to produce?

A

Osteoblasts

47
Q

What do osteoblasts do in endochondral ossification?”

A

begin secreting new bone matrix on the old cartilage matrix

48
Q

what does the vasculated primary ossfication center lead to?

A

leads to cartilage cells dying off and in their absence the remaining cartilage matrix begins to calcify

49
Q

What do the osteoblasts secrete in the primary ossification center?

A

secreting osteoid on the remnants of the calcified cartilage matrix

50
Q

what is osteoid?

A

the initial, unmineralized version of bone matrix

51
Q

What causes the osteoid to eventually become mineralized?

A

hydroxyapatite

52
Q

What does the ossification process eventually create?

A

The bone eventually thickens peripherally into compact bone
The cancellous bone in the central region is subsequently resorbed, leaving a marrow cavity which later is populated by hemopoietic tissue (blood forming cells)

53
Q

When and where does the secondary ossification center develop?

A

Develops in each epiphysis and most develop postnatally when a blood vessel grows into the epiphysis. The process of cartilage replacement mimics what is seen in the primary ossification center

54
Q

How does hyaline cartilage end up on articular surfaces?

A

Hayline cartilage is actually what is leftover after the rest of the cartilage has calcifies into bone

55
Q

What are epiphyseal plates?

A

Transverse disk of cartilage between diaphysis and epiphysis.
Required for postnatal lengthening of bone (Growth Plate)

56
Q

What are the zones in early epiphyses and epiphyseal plates?

A
zone of resting cartilage
Zone of proliferating cartilage
Zone of hypertrophied cartilage
Zone of calcifying cartilage
Zone of ossification
57
Q

What are the characteristics of the zone of resting cartilage?

A

Primitive hyaline cartilage
Cartilage cells are evenly distributed throughout zone
Uniformly small cells and not actively dividing
Not producing much matrix

58
Q

What are the characteristics of the zone of proliferating cartilage?

A

Cartilage cells here are rapidly dividing
Very active interstitial growth
Many isogenous groups visible
Large areas of newly produced matrix

59
Q

What are the characteristics of the zone of hypertrophied cartilage?

A

Also called “maturing cartilage”
Large swollen cartilage cells (still located within isogenous groups)
These cells are dying

60
Q

What are the characteristics of the zone of calcifying cartilage?

A

Cartilage cells have died and washed away
In their absence, matrix starts to change
Calcium accumulates in cartilage matrix
Matrix changes color from pink to blue
Perfect environment for bone to grow

61
Q

What are the characteristics of the zone of ossification?

A

Osteoblasts land on calcified cartilage
Convert it to bone
Bone stains a distinctive red

62
Q

Where does the majority of interstitial ossification occur?

A

In the proliferating zone

63
Q

How do bones widen?

A

Through appositional growth originating in the endosteum and periosteum

64
Q

What causes bones to lengthen?

A

Continued interstitial growth in epiphyseal plate cartilage
Balanced by loss of cartilage (calcification) on diaphyseal side of plate
Eventually cartilage replacement exceeds cartilage production leading to ossification
no further lengthening is possible after this happens

65
Q

What do osteoblasts make?

A

Bone matrix (osteoid, primitive bone)

66
Q

What is intramembranous ossification used to form?

A

flat bones and facial bones

67
Q

What causes mesenchymal cells to differentiate into osteogenic cells?

A

early vascularization

68
Q

what are osteogenic cells and what do they divide into?

A

stem cells that divide to produce osteoblasts

69
Q

What are the steps that osteoids take to reach bone?

A

osteids -> mineralized osteoid -> bone

70
Q

how does trabecular bone form?

A

Through remodeling

71
Q

What develops blood vessels and contributes to hemopoietic bone marrow?

A

intervening residual mesenchyme

72
Q

how does the complete plates of bone form in flat and facial bones?

A

Increased bone formation on the inner and outer surfaces

73
Q

what happens when bone is treated by an acidic solution?

A

the inorganic matrix is removed

74
Q

what happens when bone is treated by an extreme heat?

A

organic material is removed

75
Q

What is compact bone also known as?

A

Cortical bone

76
Q

what is compact bone?

A

hard outer shell seen particularly well in diaphysis of long bones

77
Q

what is the function of compact bone?

A

functions to “carry the load”

78
Q

what is the periosteum?

A

transitional tissue on the outer surface of compact bone

79
Q

what is osteogenic periosteum?

A

Adjacent to compact bone with osteoblasts

- provides for outward appositional growth

80
Q

what is Fibrous periosteum?

A

peripheral layer with fibroblasts

81
Q

What is the endosteum?

A

inner cellular layer (no fibrous layer) lining the marrow cavity
- provides for inward appositional growth

82
Q

what is spongy bone also known as?

A

Travecular or cancellous bone

83
Q

what is spongy bone?

A

Anastomosing lattice of bony spicules in the epiphysis and marrow cavity

84
Q

What is the function of spongy bone?

A

functions to “distribute the load”

85
Q

Where is lamellar bone found?

A

Found in both compact and spongy bone

86
Q

What is the alignment of the collagen of lamellar bone?

A

Regular parallel alignment of collagen in sheets

87
Q

what is woven bone?

A

Fetal form of bone and also seen during wound repair

88
Q

What is the alignment of the collagen of woven bone?

A

collagen is layed down in a very irregular fashion

temporary condition which will later be remodeled into lamellar bone

89
Q

What is the proferred condition of bone?

A

lamellar bone because the organization results in strength

90
Q

what zones are there in synovial joint?

A
Superficial zone
intermediate zone
deep zone
tidemark
calcified zone
91
Q

what is the superficial zone in synovial joint?

A

flattened chondrocytes adjacent to the synovial fluid

- collagen bundles oriented parallel to articular surface create smooth surface

92
Q

what is the intermediate zone in synovial joint?

A

Round, evenly distributed chondrocytes

  • disorganized collagen bundles permit deformation in response to load
  • fluid readily moves in/out of this zone in response to load
  • fluid exchange provides a vehicle for metabolic exchange for chondrocytes
93
Q

what is the deep zone in synovial joint?

A

clustered chondrocytes near the epiphyseal bone

- responsible for interstitial growth to maintain articular cartilage

94
Q

what is the tidemark in synovial joint?

A

transition line between deep zone and calcified zone

95
Q

what is the calcified zone in synovial joint?

A

Layer of calcified cartilage matrix adjacent to epiphyseal bone

  • Results from very slow but perpetual endochondral ossification
  • collagen fibers oriented perpendicular to surface anchor cartilage to bone
96
Q

What is the process of articular cartilage calcification?

A

1) Begins with small deposits ofcalcium salts
2) These coalesce as they increase in size
3) Interferes with adequate diffusion to/from chondrocytes
4) Chondrocytes die and cartilage matrix is slowly resorbed with eventual erosion to the subchondral bone

97
Q

What is the stratum fibrosum?

A

outer portion of joint capsule comprised of dense irregular CT

98
Q

Joint capsules vary in thickness which correlates with the amount of stability or mobility it provides?

A

True

99
Q

Where does the stratum fibrosum transition to fibrocarilage?

A

At insertion points on bones

100
Q

The stratum fibrosum is richly vascularized but poorly innervaed, true or false?

A

False, it is poorly vascularized but richly innervated with proprioceptive nerve endings

101
Q

What is the stratum synovium?

A

inner lining layer of capsule

102
Q

What is the intima in the stratum synovium?

A

1-3 layers of specialized fibroblasts

103
Q

What are the specialized fibroblasts in the intima of the stratum synovium known as?

A

Synoviocytes

104
Q

What are synoviocytes function?

A

responsible for producing and recycling synovial fluid and removing debris

105
Q

What is the subsynovial layer of the Stratum Synovium?

A

the highly vascular supporting Connective Tissue layer for the intima

106
Q

What is synovial fluid?

A

thin fluid film that coats articular surfaces and the stratum synovium

107
Q

What is the function of synovial fluid?

A

Lubricates internal joint surfaces to reduce friction

Provides a medium for metabolic transport to/from articular cartilage chondrocytes