Cartilage Flashcards Preview

Cell Biology > Cartilage > Flashcards

Flashcards in Cartilage Deck (37)
1

What is cartilage?

A dense supportive connective tissue that consists of cells (chondrocytes), fibers, and ground substance

2

Is cartilage vascularized?

No, no capillary bed

3

How does the lack of vascularization affect cartilage?

Limits the thickness of cartilage

Thick cartilage has vascular canals

4

What are the types of cartilage?

Hyaline, fibrocartilage, elastic cartilage

5

What are examples of hyaline cartilage?

Developing bones, growth plates, articular surfaces, respiratory tracts

6

What are examples of fibrocartilage?

Intervertebral discs, cardiac skeleton, some tendon/muscle to bone connections

7

What are examples of elastic cartilage?

Epiglottis, pinna

8

What are chondrocytes?

Chondrocytes are mature cells that are within the spaces of the cartilage extracellular matrix

9

Do chondrocytes occur singly or in groups?

Both singly and in isogenous groups

10

What are chondrocytes responsible for?

Production and Maintenance of cartilage

11

What cells differentiate in to chondrocytes?

Mesenchymal cells

12

What do chondrocytes look like?

Round with basophilic nucleus

13

When do mesenchymal cells become chondrocytes?

When mesenchymal cell is surrounded by extracellular matrix

14

What is a lacunae?

The space in the extracellular matrix that is occupied by the chondrocyte

15

Defining characteristics of lacunae

Good contrast between the chondrocyte and the matrix

Chondrocytes usually shrink more than the extracellular matrix

16

Which characteristic is used to easily define cartilage?

Presence of lacunae

17

What is ground substance made of?

Proteoglycan aggregates (made of many GAGs)

Hyaluronic acid is the most important one for binding aggregates

18

Is ground substance hydrophilic?

Yes, proteoglycans absorb 50x their dry weight in interstitial fluid

19

Why is the ground substance resilient?

Negative charge of GAGs repel each other

20

How do chondrocytes receive nutrition?

Nutrients and waste products diffuse through the extracellular matrix

Proteoglycan aggregates hold extracellular fluid which can be squeezed in and out of cartilage

21

Do chondrocytes connect?

No, chondrocytes do not contact each other

22

What is the perichondrium?

dense irregular connective tissue that surrounds cartilage

23

What are the 2 layers of perichondrium?

Inner layer is chondrogenic (cells of inner layer are chondroblasts)

Outer layer is typical fibrous connective tissue

24

Is perichondrium present on articular or fiborcartilaginous cartilage?

No

25

What are the directions of cartilage growth?

Appositional or interstitial

26

What is appositional growth?

New cartilage is deposited on the surface of existing cartilage under the perichondrium

Chondroblasts in the inner layer become trapped by their own products and become chondrocytes

27

What is interstitial growth?

Cartilage tissue expands from within the tissue

Chondrocytes within the cartilage divide and produce more cartilage

28

What are isogenous groups?

Evidence of interstitial growth

Results from division of chondrocytes in the lacunae

As the tissue grows, the cells become more separated

29

What type of collagen is present in the extracellular matrix?

Fine collagen fibers (type II)
This gives the extracellular matrix a glassy appearance

30

What color does the ground substance stain?

Basophilic

31

Chondrocytes occur randomly singly or in isogenous groups in hyaline cartilage, what are the exceptions to this?

Growth plates and articular cartilage are more structured

32

What are the zones of articular cartilage?

Superficial zone has flattened chondrocytes and collagen fibers are parallel to the joint surface

The middle zone has round lacunae and collagen fibers that arc towards the underlying bone

33

How to tell elastic cartilage from hyaline cartilage?

Elastic fibers will contrast with the ground substance

34

Where is elastic cartilage found?

E- Epiglottis, External Ear, Eustacian tube

35

What type of fibers does fibrocartilage have?

Large collagen fibers to help with tendons and ligaments, intervertebral discs and symphyses

36

How are cells arranged in fibrocartilage?

Rounded cells in lacunae and arranged in rows between collagen fibers

37

How to tell apart fibrocartilage and dense regular connective tissue?

Round cells in lacunae