Section 3 Final

Question 1

What is Diaphysis?

Answer 1

the shaft of a bone

Question 2

What is Epiphysis?

Answer 2

the end(s) of a bone

Question 3

What does Articular (Hyaline) cartilage cover?

Answer 3

ends of moveable bones

Question 4

What is the Periosteum?

Answer 4

a fibrous membrane that covers the outer portion of a bone

Question 5

What is the Medullary (Marrow) cavity?

Answer 5

space inside bone that contains marrow

Question 6

What is the Endosteum?

Answer 6

the lining of the medullary cavity

Question 7

What is the Epiphyseal plate?

Answer 7

the area that contains hyaline cartilage in growing bone, area that causes bone to elongate, becomes ossified (bone) in adults

Question 8

What are the steps of bone fracture repair?

Answer 8

(1)Hematoma forms around fracture site
(2)Granulation tissue forms
- hematoma becomes infiltrated with capillaries, fibroblasts, macrophages, osteoclasts, osteogenic cells
(3)Callus formation
- fibroblasts lay down collagen, “soft callus” is formed which is made up of fibrocartilage
(4)Remodeling
- bone tissue is laid down replacing cartilage, this forms the bony (hard) callus
- initially spongy bone is laid down, the outer portion of the bone is converted (remodeled) into compact(cortical) bone

Question 9

What’s an Osteogenic cell?

Answer 9

a stem cell that differentiates to become an Osteoblast

Question 10

What’s an Osteoblast?

Answer 10

cells that lay down collagen fibers and matrix to form bone

Question 11

What is an Osteocyte?

Answer 11

mature osteoblast, bone cells, sense the various stressors on bone

Question 12

What is an Osteoclast?

Answer 12

bone dissolving cells

Question 13

What is matrix composed of?

Answer 13

mostly Hydroxyapatite & the organic portion is mostly collagen

Question 14

What is Hydroxyapatite?

Answer 14

a calcium phosphate salt with some calcium carbonate

Question 15

What is an osteon?

Answer 15

the basic structural unit of compact bone

Question 16

Where is the Central canal located and what does it contain?

Answer 16

located at the center of the Osteon, contains vessels and nerves

Question 17

What is the Concentric lamellae composed of and what does it surround?

Answer 17

concentric layers of matrix that surround the Central canal

Question 18

What is the Lacuna?

Answer 18

the space that houses a osteocyte

Question 19

What are Canaliculi?

Answer 19

“tiny canals” that connect lacuna

Question 20

What are Perforating canals?

Answer 20

channels that contain vessels and nerves, connect adjacent osteons and osteons to the outer surface of bone

Question 21

What vitamin is Calcitriol and what is it stimulated by?

Answer 21

a form of vitamin D
stimulated by absorption of UV light

Question 22

How does Calcitriol raise blood calcium?

Answer 22

a. Increasing absorption in the Small Intestine.
b. Stimulates calcium removal from bones (Osteoclast).
c. Causing the Kidney to retain calcium in the blood.

Question 23

What Hormone lowers blood calcium levels?

Answer 23

Calcitonin

Question 24

How does Calcitonin lower blood calcium levels?

Answer 24

a. Inhibiting Osteoclast.
b. Stimulate Osteoblast (places calcium into bone).

Question 25

What does the parathyroid hormone do?

Answer 25

this hormone raises blood calcium levels

Question 26

how does the parathyroid hormone raise blood calcium levels?

Answer 26

a.Stimulating Osteoclast.
b.Causing the Kidneys to retain calcium in the blood.
c.Stimulates the production of Calcitriol.
d.Decreases Osteoblast activity.

Question 27

What’s the normal range of blood calcium?

Answer 27

9.2 to 10.4 mg/dL

Question 28

What’s Hypocalcemia?

Answer 28

low blood calcium

muscle is unable to relax, tetany

Question 29

Whats Hypercalcemia?

Answer 29

high blood calcium
** results in nerves and muscles becoming slow to respond; weakness, sluggish reflexes, poss. cardiac arrest**