ch 4

Question 1

4 main fxn of bone

Answer 1

structural support
levers for muscles/locomotion
protect organs and house bone marrow
metabolic reserve for minerals

Question 2

bone matrix composition

Answer 2

hydroxyapatite crystals
calcium phosphate
other minerals

Question 3

organic matrix can be called.. % of dry weight?

Answer 3

osteoid, 35%

Question 4

collagen type in organic matrix

Answer 4

type 1

Question 5

parts of the organic matrix

Answer 5

collagen, gag, glycoproteins

Question 6

sulfated gag parts, nonsulfated

Answer 6

chondroitin and keratin sulfates, hyluronic acid (small amounts of h2o)

Question 7

what are proteins that bind mineral to collagen

Answer 7

binding proteins

Question 8

what is the job of glycoproteins

Answer 8

1. binding proteins

2. bind matrix components to cells (sialoprotein)

Question 9

who has higher % of organic matrix

Answer 9

kids = therefore have less inorganic

Question 10

what will higher organic matrix allow for?

Answer 10

greenstick fractures and flexibility

Question 11

who has a more random collagen 1 arrangement

Answer 11

kids

Question 12

what happens to bone as we mature

Answer 12

matrix uniformity = increased stability

Question 13

what is an osteogenic cell

Answer 13

osteoprogenitor

Question 14

location of osteoprogenitor

Answer 14

endosteum and periosteum

Question 15

where are osteoprogenitors usually derived from

Answer 15

mesenchyme cells

Question 16

fxn of osteoprogenitors

Answer 16

produce: osteiod and the materials which initiate calcification of newly prod bony matrix

Question 17

what hormone do osteoprogenitors respond to

Answer 17

parathyroid hormone (PTH)

Question 18

what does the response to PTH do

Answer 18

1.secrete OPGL ( osteoprotegerin ligand)
initiates secretion of osteoclasts
2.secrete osteoclast-stimulating factor

Question 19

osteorogenitors mitosis?

Answer 19

no

Question 20

what is the mature version of osteoblast

Answer 20

osteocyte

Question 21

what does osteocyte look like

Answer 21

conforms to lacuna

Question 22

location of osteocyte

Answer 22

matrix w/ in lacuna

Question 23

what are osteocytes derived from

Answer 23

osteoblast

Question 24

fxn of osteocyte

Answer 24

1. maintain bone
2. release factors to influence osteoblast activities
3. release factors that cause creation of more osteoclasts

Question 25

osteocyte mitosis?

Answer 25

no

Question 26

where is the primary location of bone-lining cell

Answer 26

endosteum

Question 27

what are bone-lining cells derived from

Answer 27

osteoblasts mainly

Question 28

fxn bone-lining cell

Answer 28

wait : usually its a resting osteoblast

Question 29

mitosis bone-lining cell

Answer 29

no

Question 30

which cell is large and multinucleated?

Answer 30

osteoclast

Question 31

location of osteoclast

Answer 31

endosteum and periosteum

Question 32

what are osteoclast derived from?

Answer 32

granulocyte-macrophage progenitor cell

Question 33

osteoclasts are related to....

Answer 33

monocytes

Question 34

fxn of osteoclast

Answer 34

resorb bone

Question 35

where does osteoclast work?

Answer 35

subosteoclastic compartment

Question 36

inorganics are disolved by osteoclast using

Answer 36

acids then broken down using lysosomal enzymes