11/17 Histo of Cartilage Flashcards Preview

FOM Quiz 8 > 11/17 Histo of Cartilage > Flashcards

Flashcards in 11/17 Histo of Cartilage Deck (54):
1

what are the tree types of cartilage

hyalin cartilage; elastic cartilage; fibrocartilage.

2

How is Cartilage different from CT proper?

Avascular; only one cell type peresent, the chondrocyte. Type II collagen present

3

Compare the Cells in CT proper and Cartilage

CT: (Fibroblasts, adipocytes, MOs, Mast cells, Lys, Plasma cells, granulocytes. Cartilage (Chondrocytes)

4

compare the fibers in CT proper and Cartilage

CT Proper ( Type I collagen, some type III, elastic variables) Cartilage (type II collagen, type i varies elastic variable)

5

Compare the Ground substance of CT proper and cartilage

1. Both have lots of GAGs. 2. Both have lots of proteoglycans (Cartilage has lots of aggrecan found in hyaline.) 3. Adhesive glycoproteins: CT proper(fibronectin, laminin). Cartilage (chondronectin, as well as fibronectin and laminin.)

6

What is the stem cell origin of cartilage.

they are from mesenchymal stem cells.

7

What is collagen?

it is a family of proteins, ca. 30 different genes with about 25 different types of collagen but 90% of it is Type I

8

Describe Type I collagen

Helix of 3 alpha chains (alpha 1 and alpha 2): 33% glycine (about every 3rd residue) with proline and lysine that is made into prolyl hydroxylase and lysyl hydroxylase.

9

What is the neccessary component that is needed to make the hydroxylases out of proline and lysine to make collagen (proline and lysine hydroxylation)?

vitamin C and oxygen in order to perform the hydroxylase reaction with proline and lysine

10

How does the reaction that is usd to make collagen used to control oxygen?

the reaction with vitamin C to make the hydroxylates also uses oxygen and so it can be a mechanism for sensing normoxia and hypoxia

11

What is the general chemical reaction that is needed to use amino acids to make collagen?

hydroxylation!

12

What if I don't ever eat Vit. C what will happen

scurvy (general weakness, skin lesions, blood vessels fragility) where I can't do hydroxylation of amin acid and cant make collagen.

13

Describe the construction of Collagen I fibers..

Tropocollagen is packed into overlaping layers that make alpha chains that are then wrapped together into fibrils, and then these are packed into fibers, and fibers are packed into bundles that make up structures such as tendons

14

How is Type II collagen structure different from type I?

it has tropocollagen layered into tropocollagen sheets that is wrapped into triples of alpha chains that are packed together to make fibrils (just like type I). Type II then stays as a fine mesh like structure of fibrils

15

How is type III different from Type I collagen construction

Associates into Fibers but not into bundles.

16

what gives hyaline cartilage matrix its high tensile strength and resiliency?

huge proteoglycan aggregates bind a considerable amount of water and ions, giving the matrix these properties.

17

the most widely dist. cartilage in the body

Hyaline cartilage

18

Hyaline cartilage found in...?

walls of large respiratory passages; larynx; articular surfaces of bones; ventral ends of ribs

19

Transient location of hyalin cartilage

model of skeleton, epiphyseal growth plate

20

Why would hyaline cartilage appear glassy and be strong and smooth?

it is type II collegen that is not fibers by a highly hydrated matrix!

21

Describe the contents of the Hyaline cartilage matrix

The proteoglycan aggregates, GAGs and Proteoglycans (e.g. AGGRECAN) along with: Bound water; and Type II collagen fibrils; and chondronectin that attaches cells to ECM, and finally Chondrocytes that turnover and replace matrix.

22

how much of the wieght of the hyaline cartilage would be water?

75-80%

23

What is the main fiber in hyaline cartilage matrix

Type II collagen fibrils (40-70% dry weight)

24

Attaches the cells to ECM in Hyaline cartilage...?

Chondronectin

25

What turns over and replaces the matrix of hyaline cartilage

the condrocytes do! proteoglycan turnover: weeks and type II collagen: years

26

the type of cartilage that is not surrounded by perichondrium

articular cartilage

27

The surrounding around most permanent hyaline cartilage

perichondrium

28

WHAT IS perichondrium made of?

Type I collagen fibers

29

the source of the progenitor cells for cartilage

the perichondrium is the source of chondrogenic cells (progenitors) and chondroblasts for growth of new cartilage and repair.

30

the progenitor cells of collagen

chondrogenic cells

31

What will supply the nutrients and remove waste in the cartilage?

the vasculature of the perichondrium...therefore limit thickness and repair

32

The cavities where the chondrocytes reside

the lacunae

33

The functions of Cartilage

Support soft tissue; shck absorber; low friction surface; model of skeleton

33

A group of Chondrocytes in the cartilage is what?

the cell mass in the lacuna is called a Cell nest or isoginous group.

35

the cartilage cells that come form the perichondrium

chondrogenic cells and chondroblasts

36

How do you get multiple chondrocytes clumped together in the cartilage.

the chondrocytes will undergo division and all of the cells in one lacuna are clones!

37

What do chondroblasts and young chondrocytes secrete?

ECM

38

The chondroblats move into the cartilage and become...

chondrocytes

39

The dark staining area around the lacuna in the cartilage

The territorial matrix

40

What is found in the territorial matrix in cartilage that makes it stain dark?

Rich in GAGs, stains darker

41

A dark staining streak inbetween chondrocytes in the lucana

Septum

42

The lighter colored area outside of the territorial matrix in a cartilage

The interterritorial matrix

43

What are the two types of cartilage growth?

Appositional growth and interstitial growth

44

What is appostitional growth

chondroblasts in perichondrium differentiate into chondrocytes, start producing matrix and add to existing cartilage.

45

what is interstitial growth

proliferation and hypertrophy of existing chondrocytes.

46

If the Articular cartilage does not have a perichondrium, then where does repair come form?

resident chondrocytes serve as progenitors but does not repair quickly at all.

47

where do we find articular cartilage?

Lines the joints...outside of it is the synovial fluid.

48

How do you identify elastic cartilage?

it will have elastic fibers, and has more cells then matrix...more cellular, but the isogenous groups have fewer cells per group.

49

Where would you find elastic cartilage

auricle of ear, eustachian tubes, epiglottis, larynx

50

how would you identify the fibrocartilage?

very little ground substance, mostly fibers, lots of type I collagen, along with type II; no perichondrium, fibrocartilage merges with adjacent tissue

51

What is the classic area of figrocartilage?

in the pubic symphysis...right up to and fused with the bone! and the intervertebral disks.

52

the components of intervertebral disks

It has hyaline cartilage on the body of the vertebra and then anulus fibrosus that is fibrocartilage; and in the middle is the nucleus pulposus.

53

What is the nucleus pulposus?

a liquid form of fibrocartilage, with more proteoglycans and water than in the annulus fibrosus.

54

Describe the composition of fibrocartilage in the pubic symphysis if I zoom up close...

Chondrocytes surrounded by lots of collagen fibers in strands and bundles. Looks like purple spots and areas surrounded by red ropes!