Test 2

Question 1

Function of Bone

Answer 1

1. Protection of vital organs
2. Support for the body
3. The mechanical basis for movement
4. Storage of salts (calcium)
5. Continuous supply supply of new blood cells
6. Produce Growth factor storage such as Bone morphogenetic Protein (BMP)

Question 2

what is BMP

Answer 2

BMP are a growth factors that induce bone and cartilage formation utilized utilized in long bone fractures and spinal fusion.

Question 3

what is FBG

Answer 3

Produce fibroblasts Growth Factors

involoved in angiogenesis (angio-G-vessel) wound healing, embryonic development (neural, limb development)

Question 4

What are the two types of bones

Answer 4

1. Compact

2. Spongy or Cancellous

Question 5

Long Bones

Answer 5

they have a superficial thin layer of compact bone around a central medullary (marrow cavity). Within this cavity that contains marrow of adult bones, that produce all types of blood cells

Question 6

Osteoblast

Answer 6

produce cell

Question 7

Compact Bone provides:

Answer 7

strength for weight bearing

Question 8

Long Bones are designed for:

Answer 8

rigidity and attachment of muscles, ligaments.

Question 9

Cancellous bone is located:

Answer 9

near the ends of the bones in order to adapt to different angles of stress placed on the bone

Question 10

feel of the cancellous bone

Answer 10

it is spongy and lattice like with porosity greater than 70%

Question 11

Structure of the cancellous (spongy) bone

Answer 11

although quit rigid, it is weaker and less stiff than compact bone

Question 12

Trabeculae

Answer 12

fine bone spicules located in cancellous bone

• the trabecular adapt to the direction of the imposed stress on the bone, providing strength while maintaining low weight in the structure
• the high porosity gives spongy bone high energy storage capacity so that it becomes a crucial element in the energy absorption and stress distribution when loads are applied to the skeletal structure

Question 13

Between the Trabeculae is

Answer 13

marrow that produce most of the blood cells (erthryocytes)

the matrix is also laminar formation, like compact bone, however, the concentric rings are irregular and osteoblasts are more spread out, thus the lattice appearance

Question 14

Bone mass of Compact Bone

Answer 14

80% of the bone mass is dense and offers strength and stiffness to the skeleton

Question 15

Periosteum

Answer 15

• a thin white membrane that covers the outside of the bone

- specialized connective tissue that covers all of the bones

Question 16

external layer of the compact bone

Answer 16

contains numerous blood vessels to perfuse the bone

Question 17

internal layer of the compact bone

Answer 17

contains many osteoblasts that form new bone referred to as being osteogenic and are responsible for increasing the width of the bone.

Question 18

Sharpley’s Fibers

Answer 18

• located inside the compact bone
• secures the periosteum to the bone
• tendons merge with periosteum to transfer the force generated by the muscle to the bone moment
• the way that tendons and ligaments attach to the outer layer of there periosteum and transfer forces into the bone

Question 19

Endosteum

Answer 19

a membrane that lines the medullary canal and the walls of the spaces in the cancellous bone. It is thinner and less well defined than the periosteum but does not have hematopoietic and osteogenic potencies

Question 20

Osteon

Answer 20

• the basic structure of the compact bone
• lacuna located here
• Haversian Canal located here

Question 21

lacuna

Answer 21

small spaces within lamella

Question 22

Haversian Canal

Answer 22

central canal of the osteon

• Each Haversian Canal contains an arteriole, venue and nerve. Which allows blood and nerves to perfuse the bone
• Each Haversian Canal is connected by Volkmar’s Canal
• –Volkman’s Canals are connected to periosteal arteries

Question 23

Osteoblasts

Answer 23

• bone cells
• Osteoblasts of the Lacunae, Periosteum, and Endosteum deposit osteoid tissue in a concentric ring
• the bone deposition ceases when osteoid tissue begins to encroach on the blood vessels and nerves in Haversian’s canal supplying the area
• the new lamella laid in concentric rings impression the osteoblasts, which now transition into mature bone cells, are connected by small canals called CANALICULI which allows blood to flow with nutrients to each lacunae
• therefore, the bone has an elaborate canal system in order for blood to flow thou the bone
• within a few days, after the osteoid tissue is formed as concentric rings, calcimined phosphorus begin to precipitate on the osteoid tissue. The osteoid tissue covert the calcium and phosphorus to hydroxyapatite crystals, which is the material that gives bone its rigidity

Question 24

Osteocytes

Answer 24

• Mechanosensory cells of bone, involved in the transaction of mechanical loads into electrical impulses, which allows bone to grow and adapt to the body’s mechanical needs for strength
• Also appear to use some molecular signaling pathways that are familiar from other tissues, such as a generation of nitric oxide
• secrete osteopontin

Question 25

nitric oxide

Answer 25

a powerful vasodilator, which would be important when additional calcium and phosphorus is needed for increased bone production

Question 26

protoglandins

Answer 26

influence the uptake of calcium

Question 27

osteopontin

Answer 27

initiates the process by which osteoclasts develop ruffled borders, which penetrate bone then secrete enzymes that dissolve bone

Question 28

Osteoporosis

Answer 28

loss of bone mass leading to fractures - sites most affected are weight bearing structure such as vertebrae, hip and femoral neck - cancellous bone is affected due to the fact that it has a higher turnover rate - both men and women experience bone loss due to age