Chapter 6: Cartilage

Question 1

Chondroblast

Answer 1

The cells that make up the cartilage matrix in our bones

Question 2

What are the two ways the cartilage grows?

Answer 2

1. Interstital growth - grow from within the cartilage itself
2. Appositional growth- growth along the cartilage outisde edge

Question 3

_____________ the main thing that makes up the bone

Answer 3

Bone connective tissue (Osseous connective tissue)

Question 4

What are the four classes of bone?

Answer 4

1. Long bone (most common, is in the upper limbs, lower limbs, feet & toes)
2. Short bone
3. Flat bone
4. Irregular bone

Question 5

One of the main features of the long bon eis its ___________

Answer 5

Diaphysis (Shaft)

Question 6

Epiphysis

Answer 6

Knobby region at each of the long bone

Question 7

Metaphysis

Answer 7

Region of mature bone between the diaphysis & epiphysis

Question 8

Articular cartilage

Answer 8

Thin layer of hyaline cartilage covering the epiphysis at a joint surface

Question 9

Medullary cavity

Answer 9

Hollow cylindrical space within the diaphysis

Question 10

Endosteum

Answer 10

An complete layer of cells that cover all internal surfaces

Question 11

Periosteum

Answer 11

Covers the outer surfaces of the bone except for the areas covered by articular cartilage

Question 12

What are the 4 types of cells in the bone connective tissue?

Answer 12

1. Osteoprogenitor cell
2. Osteoblast
3. Osteocyte
4. Osteoclast

Question 13

Osteoprogenitor cell

Answer 13

Stem cells that came from mesechyme

Question 14

Osteoblast

Answer 14

Are responsible for creating & secreting bone (osteoid) (Also they are single nucleated cubodial ells & line the surface of the bone)

Question 15

Osteocyte

Answer 15

Maintains bone tissue & mature bone cells that repsonds to stress

Question 16

Osteoclast

Answer 16

Break down bone through bone resorption (which is a process where bone tissue is broken down & released minerals into the blood)

Question 17

The main salt crystal in the bone is ____________

Answer 17

Hydroxyapatite- which is made up of calcium phosphate & calcium hydroxide

Question 18

What is the major structure of compact bones?

Answer 18

Osteons

Question 19

What are the 4 structures of osteons?

Answer 19

1. Central (Haverison) Canal
2. Concentric Lamellae
3. Osteocytes
4. Canaliculi

Question 20

Central (Haverison) Canal

Answer 20

Is the channel that runs through the center of the osteon (Contains blood vessels & nerves)

Question 21

Concentric Lamellae

Answer 21

Are rings of connective tissue that surround the central cannel

Question 22

Osteocytes

Answer 22

Are bone cells found between lamellae

Question 23

Canaliculi

Answer 23

Are tiny channels that connect lacuna to other lacuna & to the central canal (They transport nutrients, gasses, minerals, & wastes through jap junctions)

Question 24

What are the additional structure outside the osteon?

Answer 24

1. Perforating (Volkamann’s) Canals
2. Circumferential Lamella
3. Interstitial lamella

Question 25

Perforating (Volkmann's) Cannals

Answer 25

Run perpendicular to central canals to connect adjacent osteons

Question 26

Circumferential lamella

Answer 26

Externally found underneath the periosteum or innerally found around the marrow cavity

Question 27

Interstitial lamella

Answer 27

Sits between osteons & have no central canal

Question 28

What are the features in the spongy bone?

Answer 28

1. Trabecule 2. Parallel Lamellae

Question 29

Trabecule

Answer 29

Is an opne networks of bone rods & plates

Question 30

Parallel Lamellae

Answer 30

Composed of bone matrix that run across spongy bone

Question 31

The spongy bone doesnt contain \_\_\_\_\_\_\_\_

Answer 31

Osteons

Question 32

\_\_\_\_\_\_\_\_\_\_\_\_\_ is the process of destroying the bone matrix

Answer 32

Bone resorption

Question 33

Endochondral ossification

Answer 33

Hyaline cartilage is created and then invaded by osteoblast that calcifies it (begins with hyaline cartilage and produces most bones in the body (long bones in skeleton)

Question 34

Intramembranous ossification

Answer 34

Osteoblasts differentiate directly from the mesenchyme and builds bone

Question 35

What are the phases in stage 1 of Endochondral ossification?

Answer 35

1. Zone of resting cartilage 2. Zone of proliferating cartilage 3. Zone of hypertrophic cartilage 4. Zone of calcified cartilage 5. Zone of ossification

Question 36

What are the phases in stage 2(Ossification at the cartilaginous diaphysis) of Endochondral ossification?

Answer 36

1. Osteoprogenitor cells in the perichondrium divide to become osteoblasts 2. Cartilage calcifies and forms a periosteal bone collar 3. Periosteal bud arises from the bone collar 4. . Bone is deposited from primary ossification center towards the epiphysis 5. Once at the epiphysis, same process is repeated, giving rise to a secondary ossification center. 6. Bone growth and remodeling continuous at the epiphyseal plates until early adulthood

Question 37

Bone remodeling

Answer 37

Is the continual removal of old bone (resorption) and addition of new bone tissue (deposition)

Question 38

Mechanical stress

Answer 38

Is put on the bone from weight-bearing movements and exercise

Question 39

How does hormones affect bone remodeling?

Answer 39

1. Growth hormones (somatropin) stimulates the growth of cartilage in epiphyseal plate 2. Insulin-like growth factor (IGF) stimulates the growth of cartilage in epiphyseal plate 3. Thyroid hormones stimulate bone growth by increasing metabolism of bone cells 4. - Sex hormones (estrogen/testosterone) accelerate bone growth at puberty 5. Glucocorticoids (steroid hormones) stimulate bone loss

Question 40

Stress fracture

Answer 40

Is a thin break due to repetitive stresses from physical activity (Ex: runners)

Question 41

Fractures

Answer 41

Are breaks in the bone due to unusual stress or a sudden \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Question 42

Pathological fracture

Answer 42

Can occur in diseased bone

Question 43

Simple fracture

Answer 43

Occurs when the broken bone does not go through the skin

Question 44

Compound fracture

Answer 44

Occurs when the broken bone does go through the skin

Question 45

What are the 4 stages how bone fractures are repaired?

Answer 45

1. Formation of fracture hematoma (Bleeding from damaged blood vessels, clots) 2. Fibrocartilaginous (soft) callus (forms New blood capillaries enter the clot) 3. Hard (bony) callus (Osteoprogenitor cells become osteoblasts to produce trabeculae & Trabeculae replaces the soft callus to form the hard callus) 4. Bone is remodeled