Bone

Question 1

what is Bone?

Answer 1

just a rock hard CT

Question 2

Is bone tissue living?

Answer 2

yes, it is very dynamic and well vascularized and innervated

Question 3

are the bones organs?

Answer 3

yes, they have a bunch of different types of tissues so it makes sense

Question 4

what connects bone to muscles?

Answer 4

tendons

Question 5

What connects bone to bone?

Answer 5

ligaments

Question 6

What are the functions of bones?

Answer 6

support
movement
protect
store minerals
form blood cells

Question 7

What are the different cell types in bone?

Answer 7

Mesenchymal stem cells
osteoblasts- form bone tissue
Osteocytes- mature osteoblasts that become embedded in the bone matrix
Osteoclasts- removes bone tissue (bone resorption)

Question 8

What is the bone lacunae?

Answer 8

the space occupied by an osteocyte in the matrix

Question 9

What are canuliculi?

Answer 9

the small channels within the bone matrix that interconnect the osteocytes.

Question 10

how do osteocytes interact?

Answer 10

via their gap junctions

Question 11

what is the function of osteocytes?

Answer 11

To sense strain on bone and help monitor the condition of the bone tissue.
-controls the activities of osteoblast and osteoclasts

Question 12

Which cells are multinucleated and found on the bone surfaces?

Answer 12

Osteoclasts

Question 13

What do osteoclasts create that carve out tunnels within the bone?

Answer 13

Howship’s lacunae

Question 14

What is the eventual fate of osteoclasts?

Answer 14

apoptosis

Question 15

What is the diaphysis?

Answer 15

the main middle shaft of a long bone

Question 16

What is the epiphysis?

Answer 16

the rounded end of a long bone

Question 17

What is the Metaphysis?

Answer 17

the wider portion of a long bone adjacent to the growth plate

Question 18

What is the Epiphyseal plate?

Answer 18

hyaline cartilage plate within the metaphysis of children and adolescents.
-it is necessary for elongation of bones

Question 19

What is the medullary cavity?

Answer 19

A hollow area within long bones

-the marrow cavity

Question 20

What is the periostium/endostium?

Answer 20

connective tissue found on the outer surface and inner surface of hollow bones
-contains osteogenic mesenchymal stem cells

Question 21

What is the Articular cartilage?

Answer 21

cap of hyaline cartilage found at ends of bones articulating with other bones

Question 22

What is Cortical Bone?

Answer 22

the compact one

-forms outer walls of bones

Question 23

What is the primary structure of cortical bone?

Answer 23

lamellar (layers) either in a circumferential arrangement or partial rings

Question 24

What is Trabecular bone?

Answer 24

• forms a network of bony plates or rods surrounded by bone marrow
• NO osteons are found here
• found at proximal and distal ends of long bones

Question 25

What is the center of an Osteon called?

Answer 25

Haversian Canal | -blood vessels go through this

Question 26

What is bone lengthening dependent on?

Answer 26

the Epiphyseal growth plate | -the hyaline cartilage found between the primary and secondary ossification centers

Question 27

What is interstitial growth?

Answer 27

when chondrocytes are spread out into the ECM and also increase in size

Question 28

What are the 3 parts of osteogenesis?

Answer 28

Intramembranous ossification Endochondral ossification Appositional growth

Question 29

What is Intramembranous ossification?

Answer 29

when bone is formed directly from mesenchyme | - No cartilage involvement

Question 30

What is Endochondral ossification?

Answer 30

when bone develops on a cartilage model or surface

Question 31

What is Appositional growth

Answer 31

The only way to lay down bone | - osteoblasts putting bone down on the bone surface

Question 32

What does the anatomy of a bone reflect?

Answer 32

Stresses | -bone adapts to force

Question 33

What is the purpose of Bone remodeling?

Answer 33

repair microdamage | calcium metabolism

Question 34

What are the stages of healing a fracture?

Answer 34

- Hematoma formation - fibrocartilaginous callus formation - bony callus - bone remodeling

Question 35

What are some disorders of bones?

Answer 35

Osteoporosis- low bone mass, bone resoprtion faster than bone deposition, menopause Vitamin D deficiency: necessary for calcium absorption from GI tract (osteomalacia and Rickets)