Skeletal 1000ft review

Question 1

What gives rise to new bone

Answer 1

mesenchymal stem cells

Question 2

what cells create new bone

Answer 2

osteoblasts

Question 3

What boney cells are mechanoreceptors

Answer 3

osteocytes

Question 4

What do osteoclasts do

Answer 4

reabsorb bone and assist with mineral homeostasis

Question 5

What is the periosteum and what does it contain

Answer 5

covering of the bone than contains vasculature and nerves

Question 6

What cells develop osteoblasts

Answer 6

osteoprogenator cells

Question 7

How many layers make up the periosteum

Answer 7

2

Question 8

What does the external layer of the periosteum contain

Answer 8

vasculature and nerves -> branch through volkman canals

Question 9

What is the most sensitive area of bone

Answer 9

external layer of periosteum because of nerves

Question 10

What does the internal layer of the periosteum contain

Answer 10

Osteoprogenitor cells

Question 11

How is the internal layer of the periosteum attached to the bone

Answer 11

sharpey fibers

Question 12

What makes up roughly 85% of the bone

Answer 12

compact or cortical bone

Question 13

What makes up the cortical bone

Answer 13

Haversian system

Question 14

What is the functional unit of the Haversian system

Answer 14

Osteon

Question 15

what is the lamellae

Answer 15

Central or Haversian canal surrounded by layers of matrix

Question 16

What does the lamellae contain

Answer 16

Arterial / venous blood supply, nerves, lymph

Question 17

What are lacunae

Answer 17

spaces between lamellae layers

Question 18

Where are osteocytes found

Answer 18

in the lacunae

Question 19

Why are osteocytes within the lacunae covered in fluid

Answer 19

To allow for transfer of nutrients and waste

Question 20

what are canaliculi

Answer 20

Extensions of the osteocyte that allow for nutritional exchange

Question 21

Where is the volkman canal

Answer 21

Perpendicular to the Haversian canal and contain the vasculature

Question 22

Which part of the bone is layered, mesh like formation of trabeculae

Answer 22

Spongy bone

Question 23

What covers the spongy bone

Answer 23

Endosteum

Question 24

What is the role of the spongy bone

Answer 24

Assist with metabolic demands of the bone

Question 25

What cells does the endosteum contain

Answer 25

osteoblasts and precursor cells

Question 26

Where is the endosteum found

Answer 26

Lining the inner aspect the bone covering the trabeculae lines the canals weaving through cortical bone

Question 27

Where is bone marrow found

Answer 27

within the medullary canal and within the spongy bone

Question 28

What is red marrow responsible for

Answer 28

hematopoiesis

Question 29

What is yellow marrow responsible for

Answer 29

storing fat unless trauma occurs-> then can turn into red marrow

Question 30

What does the boney matrix contain

Answer 30

Calcium binding proteins, adhesion proteins, mineralization proteins (osteocalcin)

Question 31

What is the most important building block in the body

Answer 31

Collagen

Question 32

What makes up the bone matrix

Answer 32

osteoid and minerals

Question 33

What does crystalize calcium do in the boney matrix

Answer 33

Hard support for the bone

Question 34

What do collagen fibers do in the bone matrix

Answer 34

support/strength

Question 35

What do proteoglycans do

Answer 35

Proteins that transport calcium and help organize the extracellular matrix

Question 36

What do bone morphogenic proteins do

Answer 36

assist with repair of bone and supportive structures

Question 37

What do osteoblasts secrete

Answer 37

Collagen

Question 38

What is the order of bone formation in fetal development

Answer 38

chondrocytes osteoblasts osteocytes

Question 39

What allows for mineralization of the bone

Answer 39

Calcium phosphate -> hydroxyapatite crystal

Question 40

How does PTH effect osteoblasts

Answer 40

A change in PTH will cause a release of osteocalcin which creates an osteoid

Question 41

What is an osteoid

Answer 41

non-mineralized bone

Question 42

What determines the rate of osteoclast formation

Answer 42

RANKL cells which are controlled by hormones and nutrition

Question 43

What is the progression of bone cells in the body

Answer 43

mesenchymal stem cells osteoprogenetor cells osteoblasts osteocyte

Question 44

What do osteoblasts produce

Answer 44

calcium phosphate which is then converted in hydroxyapatite and collagen

Question 45

What does transforming growth factor do

Answer 45

protein that regulates bone formation

Question 46

What stimulates bone growth

Answer 46

Pressure

Question 47

What occurs when calcium blood levels increase

Answer 47

Thyroid gland will secrete calcitonin which then stimulates calcium deposits in the bone

Question 48

What occurs when calcium blood levels decrease

Answer 48

Parathyroid gland releases PTH which causes osteoclasts to degrade bone matrix and release calcium into the blood

Question 49

What makes up the majority of bone cells

Answer 49

Osteocyte

Question 50

Where are osteocytes found

Answer 50

Encased in osteoid within the space of lacuna

Question 51

What is the purpose of cilia on osteocytes

Answer 51

To act as mechanoreceptors

Question 52

What is the role of osteocytes

Answer 52

Control calcium and phosphate levels Tell osteoclasts and osteoblasts when to alter bone formation endocrine receptor

Question 53

What is the osteoclast

Answer 53

macrophage of the bone

Question 54

How do osteoclasts break down bone

Answer 54

triggers PTH secretion Hydrochloric acid will dissolve mineral in the bone Create resorption lacunae which is irregular surface

Question 55

What happens when osteoclasts are stimulated by calcitonin

Answer 55

Release their podosomes

Question 56

Where does calcitonin come from and what is its role

Answer 56

Thyroid gland Lowers calcium blood levels

Question 57

What does the parathyroid hormone do and where does it come from

Answer 57

Parathyroid glands increases blood calcium levels

Question 58

What are the key hormones in bone development

Answer 58

Calcitonin parathyroid vitamin D synergist of PTH

Question 59

How are long bones developed

Answer 59

Via enchondral ossification from hyaline cartilage

Question 60

What area of bone allows for elongation

Answer 60

metaphysis

Question 61

What is positional bone growth

Answer 61

thickening of the bone