Cartilage and Bone

Question 1

What is the common embryonic origin of cartilage and bone?

Answer 1

Mesenchyme

Question 2

What is the order of cell development which forms bone?

Answer 2

1. Mesenchyme
2. Osteoblast
3. Osteocyte
4. Bone

Question 3

What is the order of cell development which forms cartilage?

Answer 3

1. Mesenchyme
2. Chondroblast
3. Chondrocyte
4. Cartilage

Question 4

Name 4 features of cartilage

Answer 4

1. Strong but slightly flexible
2. Withstands compression forces
3. Major role in endochondral ossification
4. Avascular

Question 5

How do chondroblasts change into chondrocytes?

Answer 5

Chondroblasts secrete ECM and become trapped inside to become chondrocytes

Question 6

How do chondrocytes exist in the matrix?

Answer 6

Enclosed in lacunae

Question 7

What are the 3 types of cartilage?

Answer 7

1. Hyaline
2. Elastic
3. Fibrocartilage

Question 8

Name 3 places hyaline cartilage is found

Answer 8

1. Articular surfaces of bone
2. Trachea + Bronchus
3. Costal cartilage

Question 9

Name 2 places elastic cartilage is found

Answer 9

1. Pinna of external ear

2. Epiglottis

Question 10

Name 3 places fibrocartilage is found

Answer 10

1. Tendon insertions
2. Pubic symphysis
3. Intervertebral discs

Question 11

What colour does hyaline cartilage stain in H&E?

Answer 11

Mottled

Question 12

What comprises the matrix of hyaline cartilage?

Answer 12

Type 2 collagen fibres embedded in a gel of proteoglycans and structural glycoproteins

Question 13

Why can hyaline cartilage work as such an effective shock absorber?

Answer 13

High water content bound to GAGs

Question 14

What does GAG stand for?

Answer 14

Glycosaminoglycan

Question 15

What is the main difference between elastic and hyaline cartilage?

Answer 15

Elastic cartilage contains elastic fibres

Question 16

What is the main difference between elastic and hyaline cartilage and fibrocartilage?

Answer 16

Fibrocartilage lacks a perichondrium

Question 17

What is the perichondrium?

Answer 17

A dense irregular connective tissue which surrounds cartilage

Question 18

What is the main type of collagen contained in fibrocartilage?

Answer 18

Type 1

Question 19

What is the usual arrangement of chondrocytes in fibrocartilage?

Answer 19

Linear

Question 20

What 3 things make up the bone matrix?

Answer 20

1. Type 1 Collagen
2. Proteoglycan aggregates
3. Glycoproteins

Question 21

What adds strength to the bone matrix?

Answer 21

Calcium phosphate in the form of hydroxyapatite crystals

Question 22

What is the function of osteoclasts?

Answer 22

Resorb bone for regeneration function

Question 23

What is the function of osteoblast?

Answer 23

Forms the bone matrix

Question 24

What is the function of osteocytes?

Answer 24

Maintains bone tissue

Question 25

Where is the exclusive location of osteoblasts?

Answer 25

Surface of bone tissue

Question 26

What does an osteoblast form from?

Answer 26

Osteoprogenitor cell

Question 27

What is the principle bone cell of an adult skeleton?

Answer 27

Osteocyte

Question 28

What connects lacuna in compact bone?

Answer 28

Cytoplasmic extensions in canaliculi

Question 29

What are the two main differences between osteocytes and chondrocytes?

Answer 29

1. Canaliculi connect osteocytes | 2. Chondrocytes can appear as clusters

Question 30

Where are osteoclasts found?

Answer 30

Howships lacunae

Question 31

What are 2 main features of osteoclasts?

Answer 31

1. Highly folded cell surface | 2. Multinucleate

Question 32

What are the two types of bone?

Answer 32

1. Compact | 2. Spongy

Question 33

How is compact bone arranged?

Answer 33

Concentric lamellae of collagen fibres around central canal containing vessels or nerves

Question 34

How can the arrangement of compact bone be referred to?

Answer 34

Osteon / Haversian System

Question 35

How is spongy bone arranged?

Answer 35

Bone organised into plates of bone called trabeculae

Question 36

What is the periosteum?

Answer 36

Dense irregular connective tissue covering outer surface of bone

Question 37

What cells are found in the periosteum?

Answer 37

Osteoprogenitor cells

Question 38

How does bone bind to periosteum?

Answer 38

Sharpey's fibres (bundles of collagen) which penetrate bone matrix

Question 39

What is the endosteum?

Answer 39

Single layer of osteoprogenitor cells and small amount of CT found just inside periosteum

Question 40

What are the 2 main functions of the endosteum?

Answer 40

1. Provide nutrients to bone tissue | 2. Provision of new bone cells