Histology: Connective Tissue- Cartilage

Question 1

What is cartilage? What is it composed of?

Answer 1

• form of connective tissue
• composed of chondrocytes and a highly specialized ECM (extracellular matrix)

Question 2

What percentage of the cartilage is the ECM? Why?

Answer 2

more than 95%,
it is a functional element of cartilage.

Question 3

Is cartilage vascular of avascular?

Answer 3

Cartilage is avascular

Question 4

What does cartilage have to have to make up for its avascularity?

Answer 4

the composition of the extracellular matrix is essential for the diffusion of substances between the chondrocytes and blood vessels (in the surrounding connective tissue).

Question 5

What is the most important cells of connective tissues?

Answer 5

fibrocytes

Question 6

What are chondrocytes?

Answer 6

fibrocytes located in the cartilage.

specific name

Question 7

What are osteocytes?

Answer 7

fibrocytes located in bones.

fibrocytes are named differently depending on what location of the organism they make up.

Question 8

What are the three major cartilage types?

Answer 8

1) hyaline cartilage
2) fibrocartilage
3) elastic cartilage

Question 9

What is hyaline cartilage made out of?

Answer 9

type II collagen fibers, GAGs, proteoglycans, and multiadhesive glycoproteins.

hey hey - 2

Question 10

What is fibrocartilage made out of?

Answer 10

type I collagen fibers, and the matrix material of hyeline cartilage

pheobi = 1

Question 11

What is elastic cartilage made out of?

Answer 11

elastic fibers, elastic lamellae, and the matrix material of hyaline cartilage.

Question 12

What is the most common type of cartilage?

Answer 12

hyaline cartilage

Question 13

How do the cells differ in the different types of cartillage? What differs between the different cartillage types?

Answer 13

cells dont differ, they are the same cell.
The only thing that changes is the ECM:
1) level of ground substance
2) fibers

Question 14

Explain the structure of hyaline cartilage. What are the spaces called? What is located within these structures? What produces the matrix? How does the matrix look? How are the major cells arranged, what is it called?

Answer 14

• between the cartilage matrix, the spaced are called lacunae,
• chondrocytes are located within the lacunae
• the ECM is produced by chondrocytes
• the EMC is homogenous and amorphous
• the EMC appears glassy
• chondrocytes are distributed:
  (a) singularity
  (b) in clusters called ISOGENOUS groups

amorphous- no clear defined shape

Question 15

How many cells are “isogenous groups” usually composed of? Why are the groups called “isogenous”?

Answer 15

• 4 cells
• there is a singular cell which divides causing the 4 cells
• group of “daughter cells”

1–> 2 –> 4

Question 16

What is a “lacunae”?

Answer 16

the specific location in which isogenous groups locate themselves to produce the ECM.

Question 17

What are the ‘covering’ connective tissue of chondrocytes called? What tissue is it made out of? What is its function?

Answer 17

• perichondrium: capsule of cartilage (dense connective tissue)
• protective property–> for protection, found in every internal organ

Question 18

What three classes of molecules does hyaline cartilage contain?

Answer 18

1) collagen mollecules
2) proteoglycan aggretates
3) multiadhesive glycoproteins

not necessary

Question 19

What three types of GAGs does the ground substance of hyaline cartilage contain?

Answer 19

1) hyaluronan (regulates integrity, development and tissue repair)
2) chondroitin sulfate (building block of cartilage)
3) keratan sulfate (hydration of cartilage)

not necessary

Question 20

Where is the perichondrium not present in synovial joints?

Answer 20

on the free, or articular surfaces of articular cartilage.

Question 21

Where is hyaline cartilage found?

Answer 21

• articular surfaces of joints (articular cartilage)
• in the rib cage (coastal cartilages)
• skeletal unit in the trachea, bronchi, arynx, and nose

Question 22

What cartilage is the nose made of?

Answer 22

hyaline cartilage. When moving the nose, only the skin moves (it is an illusion that the skin cartilage is elastic).

Question 23

What does elastic cartilage contain?

Answer 23

contains:
- components of the hyaline cartilage matrix
- elastic cartilage matrix
- dense network of branching and linked ELASTIC FIBERS

Question 24

What are the properties of elastic cartilage?

Answer 24

• elastic
• resilient
• pliable

Question 25

What is the elastic cartilage always surrounded by?

Answer 25

the perichondrium

Question 26

What does the perichondrium always surround?

Answer 26

elastic cartilage

Question 27

What is the major difference between hyeline cartilage and elastic cartilage?

Answer 27

the pattern of chondrocytes:
- hyaline: round pattern
- elastic: linear pattern

Question 28

What is the rarest type of cartilage? Where can it be found?

Answer 28

• elastic cartilage

found in:
- external ear,
- middle ear
- larynx (voice apparatus)

Question 29

What is fibrocartilage (what tissues is it composed of)? How are the chondrocytes dispersed?

Answer 29

fibrocartilage-
1) dense regular connective tissue
2) hyaline cartilage

• chondrocytes are dispersed among the collagen fibers SINGULARITY, in ROWS, and ISOGENOUS GROUPS.

fibro = pheobie= dense (asian) but said hi = hyeline and dense regular

Question 30

What are the main differences of fibrocartilage?

Answer 30

1) it is a mixture of 2 individual tissues
2) some chondrocytes are in isogenous groups with a linear pattern
other chondrocytes go individually = not in isogenous groups
3) doesnt have perichondrium (connective tissue capsule)

Question 31

What does fibrocartilage not have? Why?

Answer 31

perichondrium, due to the location (in between bones)

Question 32

Where is fibrocartilage usually found?

Answer 32

in between bones:
- invertebral discs,
- pubic symphasis,
- articular discs,
- menisci of the knee joint

Question 33

What are intervertebral disks for? What are they made of?

Answer 33

absorption of shock when moving. gives the spine resistance to compression and shearing forces.

fibrocartilage!!

Question 34

What happens to old human beings (spine)? What can be done to treat pain?

Answer 34

the fibrocartilage decreases in size and capasity of shock absorbance –> inducing pain.
has to be replaced by implants through surgery.

Question 35

How can the degree of forces on joints be reflected?

Answer 35

the amount of cartilage matrix material present