Schricker

Question 1

What does the mineral content in bone and teeth provide?

Answer 1

Stiffness and Hardness

Question 2

Besides Stiffness and Hardness, what is the other function of bone?

Answer 2

Serves as a calcium reservior

Question 3

What is bone composed of?

Answer 3

Collagen and Hydroxyapetite (50 to 60 percent)

Question 4

What is the composition of the tooth

Answer 4

Enamel: Amelogenin matrix and 90% Hydroxyapetite
Dentin: Collagen matrix and 67% Hydroxyapetite

Question 5

Describe the composite structure of bone and why it is advantageous for the bone to be a composite.

Answer 5

Composites can combine the best of 2 materials
These two structures are Collagen and HA
Collagen is tough but not strong
HA is strong but not tough AKA Brittle
Together (as a composite) they are both tough and strong

Question 6

Bone has a (Blank) mineral content than teeth.

Answer 6

Lower

Question 7

(Blank) is maintained while (Blank) is not maintained.

Answer 7

Bone

Teeth

Question 8

In regards to healing what are the properties of:
Bone
Enamel
Dentin

Answer 8

Bone: can heal
Enamel: Cannot heal but can remineralize
Dentin: Can heal in a limited capacity

Question 9

Bone is (Blank)

Answer 9

Vascularized

Question 10

During the mineralization of bone what is the role of the osteoblasts?

Answer 10

Excrete Matrix Proteins

Question 11

What agent can block mineralization and what enzyme degrades the agent?

Answer 11

Pyrophosphate blocks mineralization and Alkaline Phosphatase Degrades Pyrophospate

Question 12

What are the big three factors that influence the balance in bone remodeling?

Answer 12

Hormones
Serum Calcium
Cytokines (InterLeukins, and Tumor Necrosis Factors)

Question 13

These agents Promote resorption

Answer 13

Parathyroid Hormone
Parathyroid Hormone related proteins
Prostaglandin
Interleukin (IL) 1, IL 6 and Tumor Necrosis Factor (TNF)
Prolactin
Corticosteroids
Vitamin D

Question 14

These Factors inhibit the resorption of bone.

Answer 14

Calcium
Estrogens 
Calcitonin
Tumor Growth Factor BETA
IL 17

Question 15

Osteoblasts do what?

Answer 15

Build bone

Question 16

Osteoclasts do what?

Answer 16

Destroy bone

Question 17

What are the cell lineages of osteoblasts and osteoclasts?

Answer 17

osteoBlasts: mesenchymal stem cells
osteoClasts: Hematopoietic stem cells

Question 18

OPG leads to what?

Answer 18

Osteoperosis (holes in bone)

Question 19

RANKL leads to what?

Answer 19

Bone thickening

Question 20

What percentage of calcium is mineralized?

Answer 20

99% remainder is bound or in ionic form

Question 21

What is the total serum calcium?

Answer 21

2.2 to 2.6 mmol/L

Question 22

Percentage breakdown of SERUM CALCIUM

Answer 22

Ionized 50%
Protein bound (albumin) 40%
Citrate or Phosphate bound 10%

Question 23

What is used most often to measure serum calcium?

Answer 23

Ionic calcium levels

Question 24

Primary regulator of calcium levels

Answer 24

parathyroid hormone (Parathyroid gland)
Triggers an increase in serum calcium
Stimulated by low plasma calcium

Question 25

What are the calcium sensing receptors?

Answer 25

Found on several cell types Parathyroid Gland: Parathyroid Hormone Thyroid C Cells: Calcitonin Kidney Tubules: Regulates Calcium Excretion

Question 26

Minor hormones that regulate calcium

Answer 26

Calcitonin inhibits Bone Resorption 32 Amino Acid Protein Produced by C Cells Other hormones ~Thyroid Hormone ~Estrogen and Testosterone ~Insulin Like Growth Factors (IGF 1 and IGF 2)

Question 27

Where is Calcium absorbed?

Answer 27

Small Intestine

Question 28

Regulation of Small intesting absorbtion

Answer 28

Active Transport Regulated by Vitamin D | Transport based on Relative serum/gut levels

Question 29

Where is Calcium excreted?

Answer 29

Urine and Feces

Question 30

Regulation and regulation site for excretion?

Answer 30

Parathyroid Hormone at the Kidneys | Small Intestine govern the Large Intestine

Question 31

Vitamin D

Answer 31

Increases serum calcium Increases gut absorption of calcium Increase bone adsorption

Question 32

Vitamin D Synthesis

Answer 32

Precursor synthesized in skin Stored in Liver Converted to active form in kidney 1 alpha hydroxylase is point of regulation

Question 33

1 alpha hydroxylase stimulation

Answer 33

Parathyroid hormone low calcium low vitamin D Calcitonin

Question 34

1 alpha hydroxylase Inhibition

Answer 34

Low PTH High Serum Calcium High Vitamin D 24 Hydroxylase can inactivate Liver Precursor, 25 hydroxycholecalciferol