Bones

Question 1

What are the 4 main functions of bone?

Answer 1

Weight bearing, protection, mineral storage and blood formation

Question 2

Name the membrane covering the outside of bones.

Answer 2

periosteum

Question 3

Name the membrane covering the bone marrow segment of bones.

Answer 3

endosteum

Question 4

What is bone composed of?

Answer 4

Osteocytes, osteoblasts, osteoclasts.

Question 5

What makes a bone stiff but not brittle?

Answer 5

collagen 1

Question 6

What is the structure of cortical bone?

Answer 6

Osteons with Haversian canals which have blood vessels going through too vascularise

Question 7

What is the structure of spongy bone?

Answer 7

Made of trabeculae with bone marrow surrounding the gaps

Question 8

what are other names for spongy bone?

Answer 8

Cancellous or Trabecular

Question 9

What is the name of the canals running through a bone vertically and horizontally?

Answer 9

Haversion canal and Volkmann’s canal

Question 10

What is the lamellae (matrix) composed of?

Answer 10

Collagen 1, hydroxyapatite crystals (between collagen fibres) and water

Question 11

What is the name of long bone formation

Answer 11

Endochondral ossification

Question 12

What is the name of flat bone formation

Answer 12

Intramembranous ossification

Question 13

What happens during long bone formation?

Answer 13

Cartilage is converted to bone through ossification centres. Eventually this takes over the entire cartilage. Leaves 2 epiphysial growth plates.

Question 14

What is the name of the cartilage plates left behind in long bone formation?

Answer 14

Epiphysial growth plates

Question 15

What are osteoprogenitor cells?

Answer 15

Stem cells found in the periosteum and endosteum which can mature into osteoblasts

Question 16

What are mesenchymal cells?

Answer 16

Stem cells which divide into osteoprogenitor cells, then osteoblasts

Question 17

About Osteoclasts

Answer 17

Osteoclasts - large, multinuceated, created from hematopoeitic stem cells, break down bone by releasing acid from its ruffled border

Question 18

How are osteocytes formed?

Answer 18

Osteoblasts wrap themselves in osteoid and become osteocytes

Question 19

What is an osteoid

Answer 19

Bone marrow without any minerals

Question 20

What cell initiates the calcification of osteoid

Answer 20

Osteoblasts

Question 21

About Osteoblasts

Answer 21

Differentiated by mesenchymal and osteoprogenitor cells. Build up bone by producing osteoids and calcifying it.

Question 22

Name of communication network between osteocytes

Answer 22

Canaliculi

Question 23

What are 3 regions on long bone and where are they found?

Answer 23

Metaphysis (where epiphyseal growth plate is found), epiphysis (end), Diaphesis (main midsection)

Question 24

Condyle vs Epicondyle?

Answer 24

Condyle is smooth and round, binding bone to bone. Epicondyle binds bone to muscle, tendon or ligaments

Question 25

What is interstitial growth?

Answer 25

Growth occurring from the epiphyseal growth plates

Question 26

Which growth represents an increase in width? (what causes this?)

Answer 26

Appositional growth (from periosteum)

Question 27

What are the two types of bone growth?

Answer 27

Interstitial and apositional

Question 28

Why do we have sesamoid bones?

Answer 28

Embedded within muscle or tendons, releasing the tension in that area. Important for running

Question 29

Red bone marrow vs yellow bone marrow

Answer 29

Red bone marrow is present in bones which still produce RBC due to the haemoglobin. Yellow is inactive and yellow due to adipocytes