L15- Cartilage

Question 1

The Mesengenic Process

Answer 1

genesis of mesodermal tissues, such as bone, cartilage, muscle, marrow stoma, tendon, fat, dermis, and connective tissues, in either embryos or adult organisms§

Question 2

mesencyhmals stem cells give rise to

Answer 2

many structures e.g. bone cartilage muscle marrow adipose

Question 3

which cell forms cartilage

Answer 3

chrondrocytes

Question 4

types of cartilage (3)

Answer 4

hyaline elastic fibrocarilage

Question 5

hyaline cartilage is made out of which collagen

Answer 5

type 2 collagen

Question 6

hyaline cartilage is

Answer 6

dense containing fluid

Question 7

which GAG aggregates in hyaline cartilage

Answer 7

o Hyaluronate proteoglycan aggregates are bound to the fine collagen matrix fibres

Question 8

elastic cartilage found

Answer 8

o Tough but flexible tissue

Question 9

what forms the basic of elastic cartilage

Answer 9

o Elastic fibres and elastic lamellae (layers)

Question 10

fibrocartilage (fibrous) contains which type of collagen

Answer 10

type 1 and 2

Question 11

all types of cartilage haver matrixes containing

Answer 11

proteoglycan and hyaluronic acid.

Question 12

where is articular cartilage found

Answer 12

between bones

Question 13

chrondrocytes

Answer 13

a cell which has secreted the matrix of cartilage and become embedded in it.

Question 14

Proteoglycan structure in cartilage ground substance

Answer 14

• Similar to other connective tissue - 100 hyaluronate proteoglycan aggregates per collagen fibril (only 10 in loose connective tissue) - Makes very stiff gel-like substance

Question 15

where are chondrocytes found

Answer 15

lying in lacunas (dips)

Question 16

what do chrondrocytes do

Answer 16

lay down ECM within cell as vesicle - Fibres and GAGs/ hyaluronic acid secreted into spaces between chondrocytes- tissue expansion

Question 17

during hypertrophy of a chondrocyte the cell grows and grows until it

Answer 17

bursts and releases ECM into the rest of the ECM

Question 18

what can chondrocytes not do

Answer 18

multiply

Question 19

cell type in hyaline cartilage

Answer 19

chrondrocytes only when mature - Chondrocytes present singly or in small clusters called isogenous groups (equal origin) - Chondrocytes within isogenous groups separate as they lay down ECM

Question 20

isogenous groups

Answer 20

Chondrocytes present singly or in small clusters

Question 21

hyaline and fetal development

Answer 21

hyaline cartilage is the precursor model of those bones that develop by endochondral ossification

Question 22

as bone develops hyaline caritlage

Answer 22

remains are articular surgaves (between bones) and at the epiphyseal plate

Question 23

where is hyaline cartilage found

Answer 23

• Knees - Hips - Larynx and trachea - Costal cartilage - Articular tissues of joints e.g. knees

Question 24

Articular tissues of joints

Answer 24

o Ankle o Knees o Should o Wrist o elbow

Question 25

what assicts resileince to repeated appliction of pressure in hyaline cartilage

Answer 25

hyaluronic acid- - Matrix is solid and firm but also pliable

Question 26

are blood vessels found in hyaline cartilage matrix

Answer 26

no- simple diffusion

Question 27

how can hyaline cartilage grow (2)

Answer 27

apposition growth interstitial growth

Question 28

perichondrium covers the

Answer 28

margins of hyaline cartilage

Question 29

appositional grrwth

Answer 29

growths from the periphery

Question 30

interstitial growths

Answer 30

growth from the centre

Question 31

perichondrium is what sort of connective tissue

Answer 31

dense connective tissue

Question 32

outline appositional growth

Answer 32

Grows from the perichondrium (margin of the cartilage) - Grows from precursor cells in to chondroblasts o Chondroblasts grow and grow away from the edge- appositional growth (growth from the periphery)

Question 33

chondrocytes produce and maintain their own

Answer 33

extracellular matrix

Question 34

Hyaline Example:

Answer 34

the tracheal wall - Hyaline cartilage forms C shape tracheal cartilages - Cartilage tube reinforces trachea and helps to protect and maintain the airway - Lined with pseudostratified ciliated epithelial

Question 35

do chondrocytes proliferate ina dults

Answer 35

no- damage is irreversible e.g. rheumatoid arthriitis

Question 36

cell type in elastic cartilage

Answer 36

only chondrocytes in mature elastic cartilage. Also contains elastic fibres.

Question 37

where is elastic cartilage found

Answer 37

1) Pinna of the ear 2) Eustachian tube 3) The Epiglottis has great resiliance ot rebound

Question 38

elastic cartilage grows via

Answer 38

appositional growth

Question 39

cartilage can also be produced via

Answer 39

Interstitial growth - chondrocytes grow and divide and lay down more matrix inside the existing cartilage.

Question 40

when does interstitial growth occur

Answer 40

This mainly happens during childhood and adolescence.

Question 41

in elastic cartilage staining

Answer 41

lots of dark staining due to abundance fo elastic fibres lying in the ECM

Question 42

cartilage hisotlogy

Answer 42

will look like empty cells the elastic cartilage cells (chondrocytes) do not exist- big holes where cells used to be - Cells have already laid down all fibroelastic cartilage- therefor it apoptosis

Question 43

elastic cartilage in the ear is produced via which form of growth

Answer 43

interstitial

Question 44

cells in fibrocartilage

Answer 44

Chondrocytes and fibroblasts - A combination of dense regular connective tissue and hyaline cartilage - Cells distributed in rows (like tendons)

Question 45

in fibrocartilage there is no

Answer 45

- No surrounding perichondrium

Question 46

where is fibrocartilage found

Answer 46

- Intervertebral disc- discs between the spine o Impact - Articular dics of the sternoclavicular and temporomandibula joints - The menisci of the knee joints - Pubic symphysis

Question 47

role of fibrocartilage

Answer 47

Has the resilience to act as a shock absorber and to resist shearing forces

Question 48

in a histology stain of fibrocartilage

Answer 48

lots of collagen fibres - Rounded chondrocytes are arranged in rows or as isogenous groups - Relatedly small number of elongated fibroblast – red arrows point to elongated fibroblast nuclei

Question 49

chondrocyte will nuclei are

Answer 49

still alive and producing ECM, waiting to burst to lay down more ECM