Cartilage Histology

Question 1

chondroblasts

Answer 1

cells that secrete cartilage matrix; have mitotic capabilities

Question 2

chondrocytes

Answer 2

mature cartilage cells in lacunae; come from the chondroblasts; surrounded by and maintain matrix

Question 3

what type of collagen is predominant in cartilage

Answer 3

type II

Question 4

hyaline cartilage

• surrounded by what
• contains what type of collagen
• location

Answer 4

• perichondrium
• type II collagen
• articular cartilage, larynx, trachea, ribs, embryonic, development

Question 5

elastic cartilage

• made of what
• surrounded by what
• contains what type of collagen
• location

Answer 5

• consists of hyaline cartilage plus elastic fibers
• surrounded by perichondrium
• type II collagen
• external ear, epiglottis, auditory tube

Question 6

fibrocartilage

• made of what
• surrounded by what
• contains what type of collagen
• location

Answer 6

• combo of hyaline cartilage and dense regular CT
• NO perichondrium
• type I collagen and type II via hyaline cartilage
• intervertebral discs, pubic symphysis, TMJ

Question 7

isogenous groups

• what are they
• where are they found

Answer 7

2 or 3 chondrocytes forming together in a group

- found in hyaline, elastic, and fibrocartilage

Question 8

territorial matrix

Answer 8

darkly stained tissue in hyaline cartilage surrounding isogenous groups

• high in GAGs
• consists of type II collagen

Question 9

interterritorial matrix

Answer 9

lightly stained tissue surrounding the darker stained territorial matrix

• consists of more collagen type II
• fewer proteoglycans

Question 10

epiphyseal plate

Answer 10

hyaline based “growth plate”

Question 11

perichondrium

• made of what
• surrounds what
• source for what
• other function

Answer 11

dense irregular connective tissue

• surrounds hyaline and elastic cartilage
• source of new cartilage cells
• nutrients diffuse through this

Question 12

fibrous layer of perichondrium

Answer 12

outer layer that produces type I collagen and elastin

- has more of the vasculature

Question 13

chondrogenic layer of perichondrium

Answer 13

inner layer that differentiates into chondroblasts and secretes type II collagen

Question 14

function of fibrocartilage

Answer 14

withstands compression and shearing forces

Question 15

appositional growth chondrogenesis

• what is it
• location
• process

Answer 15

“rings of a tree growth”; forms new cartilage on the surface of existing cartilage; increase in girth of cartilage
- occurs within inner layer of perichondrium
cells –> chondroblasts –> secrete type II collagen and ground substance

Question 16

interstitial growth chondrogenesis

• what is it
• location
• features

Answer 16

less common
chondrocytes divide within the lacunae which creates new isogenous groups; increase in length of cartilage
- occurs within a cartilage mass in lacunae
- secrete more matrix
- avascular process

Question 17

components of the cartilage matrix

Answer 17

type I collagen, type II collagen, elastin fibers, ground substance

Question 18

cartilage repair

Answer 18

• limited capacity due to avascular nature
• facilitates healing of bone fracture
• ability is age dependent

Question 19

repair cartilage

Answer 19

forms in cartilage repair when perichondrium is involved

• contains type I and II collagen
• can stimulate bone growth in some cases

Question 20

articular capsule of synovial joints

Answer 20

outer fibrous layer made of dense regular connective tissue that surrounds and strengthens the joint
- contains extrinsic and intrinsic ligaments

Question 21

difference between extrinsic and intrinsic ligaments in the articular capsule

Answer 21

extrinsic are separate from the capsule and intrinsic are part of the fibrous capsule

Question 22

articular cartilage in synovial joints

• made of
• function
• vasculature?
• nourishment source

Answer 22

• hyaline cartilage
• reduces friction
• avascular, lacks nerve supply
• nourished by synovial fluid

Question 23

synovial membrane (synovium) in synovial joints

• location
• function
• vasculature?
• produces what
• other features

Answer 23

• lines joint cavity except for articular cartilage
• lubricates articular cartilage
• vascular
• synovial fluid
• regenerative
• absorbs shock

Question 24

Synoviocytes

Answer 24

make up the synovial membrane; play a crucial role in the pathogenesis of chronic inflammatory diseases
- two types:
type A macrophage-like synovial cells
type B fibroblast-like synovial cells

Question 25

type A macrophage-like synovial cells in synovial joints

Answer 25

type of synoviocyte - phagocytic, regulate inflammatory events, clear articular cavity of debris - contain lysosomes - 25% of cells lining synovium

Question 26

type B fibroblast-like synovial cells in synovial joints

Answer 26

type of synoviocyte - produce synovial fluid and hyaluronate - lubricates and nourishes the articular cartilage

Question 27

superficial zone of articular cartilage - chondrocyte characteristics - how do the collagen fibers run

Answer 27

- small and flattened chondrocytes parallel to the surface | - collagen fibers run parallel to the surface

Question 28

intermediate zone of articular cartilage - chondrocyte characteristics - how do the chondrocytes occur - how do the collagen fibers run

Answer 28

- slightly larger and round chondrocytes - chondrocytes occur both alone and in isogenous groups - collagen fibers take oblique course through matrix

Question 29

deep zone of articular cartilage - chondrocyte characteristics - how are the chondrocytes arranged - how do the collagen fibers run

Answer 29

- large chondrocytes - chondrocytes form radial columns; stacks are oriented perpendicular to the articulating surface - fibers follow orientation of chondrocyte columns

Question 30

calcified zone of articular cartilage - where is it - how does it stain

Answer 30

- rests on underlying cortex of bone | - stains darker than other layers

Question 31

Osteoarthritis

Answer 31

degenerative joint disease characterized by chronic joint pain, various degrees of joint deformity, and destruction of the articular cartilage - commonly affects weight-bearing joints (knees, hips, lumbar vertebrae, hand and foot joints)

Question 32

early stages of osteoarthritis

Answer 32

superficial layer of the articular cartilage is disrupted

Question 33

late stages of osteoarthritis

Answer 33

destruction of the cartilage extends to the bone, where the exposed subchondral bone becomes a new articular surface - progressive reduction of mobility and increased pain

Question 34

ground substance

Answer 34

amorphous gel material that fills the spaces between fibers and cells in the ECM - composed of proteoglycans