Bone composition

Question 1

What is the bone matrix made up of/percentages?

Answer 1

Water - 25%
Organic protein fibres (mainly collagen 1) - 25%
Crystallised mineral salts - 50%

Question 2

Name the 2 different types of bone tissue

Answer 2

Compact bone and spongy bone

Question 3

What is spongy bone arranged in

Answer 3

Trabeculae

Question 4

What is found in spaces between trabeculae?

Answer 4

Bone marrow

Question 5

Where in the bone is spongy bone found?

Answer 5

In the middle

Question 6

Where in the bone do you find compact bone

Answer 6

On the outer layer

Question 7

What is compact bone organised into?

Answer 7

Osteons

Question 8

What is found at the centre of each osteon?

Answer 8

A canal forming layers called lamellae

Question 9

What are the spaces between lamella layers called@?

Answer 9

Lacunae

Question 10

Where are osteocytes found?

Answer 10

Lacunae

Question 11

Name the 5 types of bones

Answer 11

Long, flat, short, sesamoid, irregular

Question 12

Name the 4 cells found in bones

Answer 12

Osteocytes, osteoblasts, osteoclast and osteoprojenitor cells

Question 13

What do osteoprojenitor cells differentiate to

Answer 13

Osteoblasts

Question 14

Where are osteoprojenitor cells found

Answer 14

Periostium and endiostium

Question 15

What do osteoblats do

Answer 15

Build up bone

Question 16

How do osteoblasts produce bone matrix

Answer 16

Osteoblasts produce bone matrix by synthesising/secreting collagen fibres and other organic components. This dephosphorylates molecules initiating the calcification of bone matrix by depositing calcium phosphate.

Question 17

How is an osteoid formed

Answer 17

One bone matrix is calcified, molecules react with eachother to form rigid but flexible bone tissue called osteoid

Question 18

What do osteoblasts differentiate into

Answer 18

osteoclasts

Question 19

Where do osteoblasts form in a cell

Answer 19

On the outer layer of a cell

Question 20

Where are osteocytes found?

Answer 20

Osteocytes are found entrapped in their own matrix in mature bone

Question 21

What is the function of osteocytes?

Answer 21

To maintain the cellular activities of bone

Question 22

Are osteoclasts multinucleated?

Answer 22

Yes

Question 23

Do osteocytes secrete matrix?

Answer 23

No

Question 24

Describe the membrane of an osteoclast

Answer 24

Face bone and releases lyosomal matrix and enzymes that digest bone/protein material

Question 25

What is the function of osteoclasts

Answer 25

To remove old bone tissue