Njds Histology - Cartilage

Front 1

QUESTION: What type of connective tissue is Cartilage?

Back 1

ANSWER:

- Rigid but uncalcified matrix
- avascular

Front 2

QUESTION:

How does Cartilage follow the model of other connective tissues?

Back 2

ANSWER:

- has cells lying in an intercellular matrix (fibers + ground substance)

Front 3

QUESTION:

What are the cells in the intercellular matrix, and what are the matrix fibers?

Back 3

ANSWER:

The cell types are chondroblasts and chondrocytes.

The matrix fibers are type I collagen, type II collagen and elastic fibers

Front 4

QUESTION:

What is the ground substance made up of?

Back 4

ANSWER:

Proteoglycans and adhesive glycoproteins, chondronectin is the most important

Front 5

QUESTION:

What are the 3 types of Cartilage?

Back 5

ANSWER:

Hyaline - most prevalent *
Elastic
Fibrocartilage

Front 6

QUESTION:

What are the 3 locations where Hyaline cartilage can be found?

Back 6

ANSWER:

1- respiratory conducting passageways
2- tissue that makes up prenatal long bones
3- covers epiphyses of adult long bones

Front 7

QUESTION:

What are the corresponding functions of Hyaline cartilage?

Back 7

ANSWER:

To maintain the patency of respiratory conducting passageways, permit growth of fetal skeleton, provide a model for developing long bones, to provide a smooth surface on articular surfaces

Front 8

QUESTION:

What does cartilage arise from?

Back 8

ANSWER:

mesenchyme

Front 9

QUESTION:

Describe the process of cartilage development

Back 9

ANSWER:

mesenchymal cells divide - become closely packed, spherical chondroblasts. They secrete cartilage matrix. Chondrocytes are chondroblasts surrounded by cartilage matrix. They continue secreting matrix and are pushed apart.

Front 10

QUESTION:

Where are chondrocytes located in the cartilage?

Back 10

ANSWER:

lacunae, which are small cavities within the matrix

Front 11

QUESTION:

In Interstitial (endogenous) growth, what happens in young cartilage?

Back 11

ANSWER:

-chondrocytes retain their mitotic potential and continue to divide
- each dividing cell produces a small group of cells close to one another

Front 12

QUESTION:

What are isologous or isogenous groups (or nests)?

Back 12

ANSWER:

Small groups of chondrocytes arising from the proliferation of a single parent cell

Front 13

QUESTION:

What does the mesenchyme surounding developing cartilage become?

Back 13

ANSWER:

its perichondrium

Front 14

QUESTION:

What is perichondrium?

Back 14

ANSWER:

A layer of vascular fibrous connective tissue surrounding fragments of cartilage, provides nutritional needs by diffusion

Front 15

QUESTION:

What does the inner layer of perichondrium contain?

Back 15

ANSWER:

chondroblasts which are chondroprogenitor cells

Front 16

QUESTION:

What happens in Appositional growth?

Back 16

ANSWER:

Chondroprogenitor cells divide and become chondrocytes, subperichondrial cartilage is deposited on the surface of the cartilage.

Front 17

QUESTION:

What is the shape of young chondrocytes?

What is the shape of older chondrocytes?

Back 17

ANSWER:

Young- near the surface of cartilage, relatively flat (ellpitical).

Older- more spherical, they are in lacunae within cartilage matrix

Front 18

QUESTION:

What happens to living chondrocytes during tissue preparation? What happens?

Back 18

ANSWER:

-They completely fill the lacunae but shrink during tissue preparation

- space forms between chondrocyte and cartilage immediately around lacunae

Front 19

QUESTION:

Characteristics of active chondrocytes?

Back 19

ANSWER:

- large, spherical, vesicular nuclei

- synthesize hyaline cartilage matrix

Front 20

Why is hyaline cartilage matrix BASOPHILIC?

Back 20

because of its type II collagen fibers and heavily sulfated ground substance

Front 21

Collagen is almost _____ of the dry weight of cartilage.

Back 21

half

Front 22

Compared to Type I collagen, what does Type II collagen contain more of?

Back 22

Hydroxylysine (which is basophilic)

Front 23

Chondroitin sulfate is ______, so it is basophilic.

Back 23

Acidic

Front 24

Why is the capsule (territorial matrix) bordering the lacunae intensely basophilic?

Back 24

It is RICHER in glycosaminoglycans and POORER in collagen than the interterritorial matrix

Front 25

What gives the matrix its rigidity?

Back 25

Proteoglycan aggregates:
- hyaluronic acid chains link core proteins of many proteoglycan monomers
- chondroitin sulfate side chains bind to collagen

Front 26

How do the large aggregate (or aggrecan) molecules attract water molecules?

Back 26

they create negative charges that attract the cation, sodium, and water is attracted. The heavily hydrated matrix resists compression

Front 27

How much of the wet weight of cartilage is water?

Back 27

80%

Front 28

What are the effects of the avascularity of cartilage matrix?

Back 28

Its vitality depends on diffusion of nutrients from surrounding tissues, limiting the size of some chondroid structures.

Front 29

What are the properties of Elastic cartilage?

Back 29

Contains both elastic and collagen fibers

Front 30

What is the function of elastic cartilage?

Back 30

Provides support coupled with flexibility and elasticity.

Front 31

Locations of elastic cartilage?

Back 31

External ear, auditory tube, epliglottis, some laryngeal cartilages

Front 32

What else does the cartilage matrix contain?

Back 32

- adhesive glycoproteins
- chondronectins (link cells to collagen
- glycosaminoglycans

Front 33

How does elastic cartilage look in its fresh condition?

Back 33

Yellow

Front 34

Describe the staining properties of the elastic fibers

Back 34

resorcin fushsin- intensely purple

Verhoeff hematoxylin- black
orcein- red/brown

Front 35

Does Fibrocartilage exist independently? What does it lack?

Back 35

No, it does not exist independently- lacks a perichondrium.

Front 36

What are the features of Fibrocartilage?

Back 36

Has features of both hyaline cartilage and dense fibrous connective tissue, may blend into adjacent tissues

Front 37

How does the matrix of Fibrocartilage stain, and why?

How are the chondrocytes oriented?

Back 37

Slightly eosinophilic (because of type I collagen content)

There are rows of chondrocytes in lacunae.

Front 38

Describe the type I collagen fibers; what are they similar to?

Back 38

Type I collagen fibers are in dense bundles, similar to those in dense fibrous connective tissue

Front 39

Function of fibrocartilage?

Back 39

strong support, tensile strength

Front 40

Where can you find fibrocartilage?

Back 40

- Intervertebral discs
- Intra-articular discs
- attachments of tendons and ligaments to bone
- symphysis pubica

Front 41

Where is fibrocartilage best visualized- what structure is formed here?

Back 41

Intervertebral discs, it forms the annulus fibrosus which surrounds the gelatinous nucleus pulposus (in concentric layers, blends into adjacent hyaline cartilage)