Cartilage Flashcards Preview

Histology > Cartilage > Flashcards

Flashcards in Cartilage Deck (39):
1

Main types of collagen

Type I, II, III and IV

2

Type I collagen

Most abundant, widely distributed

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Type II collagen

- Hyaline and elastic cartilage
- Fibres thinner than type I

4

Type III collagen

Reticular fibres

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Type IV collagen

- Found in the basal lamina
- Does not form fibrils

6

What type of collagen is found in dense regular and irregular connective tissue

Type I

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Where is the basal lamina

Between the epithelia and underlying supporting connective tissue

8

What is the function of the basal lamina

A selective barrier to the passage of materials between the epithelium and supporting tissue

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What is the basal lamina involved in the control of

Epithelia growth and differentiation

10

What is the basal lamina composed of

GAGs, type IV collagen and glycoproteins

11

What other disaccharide polymer are many proteoglycans non convalently linked to

Hyaluronan

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What stabilises the interaction between proteoglycans and hyaluronan

Link proteins

13

Describe cartilage

- Semi-rigid connective tissue
- Consists of scattered cells surrounded by amorphous appearing extracellular matrix

14

Composition of extracellular matrix of cartilage

Contains type II collagen which provides mechanical stability and GAGs which resist deformation by compression

15

Cartilage formation

- Differentiation of primitive stellate mesenchymal cells into chondroblasts
- These cells proliferate and aggregates of cells grow and begin to synthesis ground substance and fibrous extracellular material
- Cells mature into chondryocytes and these maintain integrity of cells

16

How dos cartilage get its nutrition

Through diffusion of metabolites

17

What are the cells found within cartilage called

Chrondrocytes

18

Characteristics of chondrocytes

- Live in the lacuna
- Vary in shape
- Flattened near the edge of cartilage
- Rounded near the centre
- Secrete and maintain extracellular matrix

19

What happens if vascular supply around cartilage is disrupted

The cells die, blood vessels invade the matrix and the matrix is phagocytosed and replaced by scar tissue

20

Composition of EMC

75% water and 25% organic materials

21

What is the organic material made from

60% type II collagen and 40% proteoglycan aggregates

22

Important glycoprotein in the cartilage matrix

Chondronectin

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Function of chondronectin

Promotes the adherence of chondrocytes to the matrix of collagen

24

The matrix in the area around the chondrocyes is

Particularly high in proteoglycans and is known as the territorial matrix

25

Matrix at a distance from chundrocytes

Has fewer proteoglycans and is known as the interterritorial matrix

26

Connective tissue that surrounds the cartilage

Perichondrium

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Layers of the perichondrium

Outer fibrous layer of dense connective tissue and an inner chondrogenic layer which provides now chondroblasts to the adjacnt cartilage

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What does the perichondrium contain

Blood vessels that supply nutrients to the whole of the avascular cartilage

29

How does cartilage grow

Appositional growth at the edge and interstital growth with the matrix

30

What are the types of cartilage

Hyaline cartilage, elastic cartilage and fibrocartilage

31

Hyaline cartilage

Blue-white in colour and translucent. Most common form

32

Elastic cartilage

Light yellow in colour. Addition of elastic fibres makes it flexible

33

Fibrocartilage

White in colour. Hybrid between the other two. Has bands of densely packed type I collagen interleaved with rows of chondrocytes surrounded by small amounts of cartilaginous ECM

34

Where is hyaline cartilage found

Articular surfaces, tracheal rings, costal cartilage, epiphyseal growth plates and the precursor to bone in the foetus

35

What type of cartilage is found at a synovial joint

Hyaline cartilage

36

Where is elastic cartilage found

Pinna of the ear, epiglottis and auditory tube

37

Where is fibrocartilage found

Intervertebral discs, where the tendon inserts into the bone (enthesis) and pubic symphysis

38

What effect does age have on cartilage

Chondrocytes from older animal produce shorter proteoglycans which may lead to lessened ability to attract water molecules and decreased resistance to compression = damage of articular cartilage and osteoarthritis

39

Characteristics of cartilage

- Deformable
- Permeable
- Appositional and interstitial growth
- Cells in the matrix nourished through diffusion