Bone

Question 1

Osteoblasts

Answer 1

Bone forming cells

Question 2

Osteoclasts

Answer 2

Bone removing cells

Question 3

Osteocytes

Answer 3

The mature cells

Question 4

Where are osteocytes located?

Answer 4

Lacunae

Question 5

The organic matrix of bone provides what two things?

Answer 5

Tensile strength and flexibility

Question 6

Mineral gives bone what?

Answer 6

Hardness

Question 7

Endochondral ossification

Answer 7

when bone replaces the cartilage
-has physes and articular-epiphyseal complexes

Question 8

What factors affect endochondral ossification?

Answer 8

GH, insulin-like growht factor, thyroxine, vitamin D

Question 9

What is intramembranous ossification?

Answer 9

Bone forming within fibrous tissue (No cartilage model)

Question 10

New bone (woven bone) turns into…

Answer 10

lamellar bone

Question 11

Only mechanism of getting rid of bone

Answer 11

osteoclastic bone resorption

Question 12

Osteoclastic bone resorption is stimulated by?

Answer 12

Parathyroid hormone, bone tension, interleukins

Question 13

T/F? Bone is always being resorbed and formed.

Answer 13

True

Question 14

What does Wolff’s law state?

Answer 14

bone remodels in order to accommodate the stress it encounters

Question 15

Three layers of the joint capsule

Answer 15

1. outer fibrous layer
2. loose fibrovascular layer
3. synoviocyte layer (single layer)

Question 16

Nutritional source for the chondrocytes

Answer 16

Synovial fluid

Question 17

Bone deformities/abnormalities of development can be due to what factors?

Answer 17

abnormal cartilage model, inadequate growth, genetic or acquired, defect EO at the physis or AE

Question 18

Chondrodysplasia

Answer 18

Angular deformities, dwarfism

Question 19

What is osteochondrosis?

Answer 19

focal defect in endochondral ossification, necrosis of articular cartilage
-lesion can’t withstand weight

Question 20

What does necrosis of AC lead to often times?

Answer 20

osteoarthritis

Question 21

Loss of bone =

Answer 21

resorption > remodeling

Question 22

An example of diffuse loss of bone?

Answer 22

Osteoporosis or osteopenia

Question 23

What are a few causes of diffuse loss of bone?

Answer 23

disease, poor nutrition, hyperparathyroidism

Question 24

An example of focal bone loss?

Answer 24

bone lysis

Question 25

What causes focal bone loss?

Answer 25

chronic inflammation, neoplasia

Question 26

Inflammation in the middle of the bone marrow is?

Answer 26

osteomyelitis -purulent exudate

Question 27

What type of cells should you never see in bone?

Answer 27

epithelial cells

Question 28

Increased amount of bone produced in a place it isn't supposed to be

Answer 28

hyperostosis

Question 29

Abnormally-dense bone form the failure of osteoclast activity

Answer 29

osteosclerosis

Question 30

death of bone cells

Answer 30

osteonecrosis

Question 31

What causes osteonecrosis?

Answer 31

ischemia toxins heat/cold

Question 32

Necrotic bone stays in place until???

Answer 32

osteoclasts get rid of it

Question 33

A piece of necrotic bone that is walled off and by itself

Answer 33

sequestrum

Question 34

What happens if there is a fracture through the physis?

Answer 34

stunts growth, premature closure/abnormal growth

Question 35

How do horses commonly get cranial hemorrhage?

Answer 35

hit their occipital bone and fracture the BASISPHENOID bone after flipping on their back

Question 36

What is the first step in bone healing when there is a fracture?

Answer 36

Hematoma at fracture site, then necrosis at the edges of broken bone

Question 37

What is a callus?

Answer 37

This soft callus is made of cartilage and fibrous tissue, and it replaces the blood clot that formed earlier. -first soft, then hardens over time

Question 38

A bone needs ________ to survive

Answer 38

blood supply

Question 39

Osteomalacia

Answer 39

softened bone, osteoid

Question 40

T/F? Osteomalacia happens in young animals?

Answer 40

No, adult animals only with closed physes

Question 41

What can cause osteomalacia?

Answer 41

Calcium deficiency, vitamin D deficiency

Question 42

T/F? Adult animals get rickets.

Answer 42

False. Young animals with OPEN physes only

Question 43

What is rickets?

Answer 43

softened, bowed bones due to enlarged osteochondral junctions. -Thickened physis

Question 44

What is a cause of rickets?

Answer 44

Vitamin D, calcium defiencies, or too much phosphorous

Question 45

What is fibrous osteodystrophy?

Answer 45

bone changes caused by too much parathyroid hormone stimulation -osteoclasts getting too much signal from the PT to break down bone for Ca+

Question 46

What are two mechanisms of fibrous osteodystrophy?

Answer 46

Nutritional and renal