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Flashcards in Bone cells Deck (78)
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1

True or false; bone is another type of connective tissue but is harder and less flexible than cartilage

true

2

What are the 4 main functions of bone

Structural support
Levers for muscle
Protect organs/house bone marrow
Metabolic reserve for minerals

3

65% of the dry weight of bone comes from where?

inorganic matrix

4

What makes up the inorganic matrix of bone

(minerals)
Hydroxyapatite crystals
calcium phosphate
other minerals

5

35% of the dry weight of bone comes from where?

organic matrix

6

80-90% of the organic matrix is made of what?

Collagen (primarily type 1)

7

True or false; the organic part of bone has a highly organize fiber arrangement

true

8

What are the 3 parts of the organic matrix of bone

Collagen (primarily type 1)
GAGs
Glycoproteins

9

What are the 2 types of GAGs in the organic matrix of bone

Sulfated (more numerous) - chondroitin and keratin
Non-sulfated - Hyaluronic acid

10

What are binding proteins

proteins that bind minerals to collagen

11

True or false; vitamin D stimulates arrangement of minerals

true

12

True or false; there is a higher amount of organic matrix in adult bone compared to children

false; more in children (aka more flexible - greenstick fractures)

13

True or false; the arrangement of bone is more random in childhood and increases uniformity as we age

true

14

Are osteoprogentic cells mitotic?

Yes

15

What is the function of osteoprogenic cells? What are their appearance?

change into osteoblast

flat

16

What is the location of osteoprogenitor cells? What are they derived from?

Located in endosteum and periosteum

Derived mainly from mesenchyme, but sometimes chondrogenic

17

What are the appearance of osteoblast? Where are they located?

Cuboid to columnar

Endosteum and periosteum

18

What are osteoblast derived from? What are their functions?

Derived from osteoprogenitor

Produce osteoid, materials (matrix vessicles) - initiates calcification of newly produced boney matrix
And respond to PTH (parathyroid hormone)

19

Are osteoblast mitotic?

No

20

What response do osteoblast have to PTH (parathyroid hormone)

Secrete factor that creates more osteoclasts
Produce enzymes to condition bone for osteoclast activity

21

What is the appearance of osteocytes

conforms to lacuna

22

What is the location of osteocytes? What are they derived from?

Surrounded by bony matrix

Derived from osteoblast

23

What are the functions of osteocytes

Maintain and monitor bony matrix

Release factors to influence osteoblast activity, and cause creation of more osteoclasts

24

Are osteocytes mitotic?

NO

25

What is the appearance and location of bone-lining cells? What are they derived from?

Flat

Endosteum and periosteum

Usually from osteoblast, sometimes osteocytes

26

What is the function of bone-lining cells

to wait and become osteoblast when needed

27

Are bone-lining cells mitotic?

NO

28

What is the appearance and location of osteoclasts? What are they derived from?

Large and multinucleated

Endosteum and periosteum

Pre-osteoclast from bone marrow; related to monocytes

29

What is the function of osteoclasts

reabsorb bone (highly specialized)

30

Where does the mechanism of bone reabsorption take place?

Subosteoclastic compartment