Bone Basics

Question 1

5 categories of bone function

Answer 1

support, protection, movement, resivoir, hematopoiesis

Question 2

3 supports

Answer 2

weight of body, teeth with pressure, organ and other tissues

Question 3

3 protections

Answer 3

skull- brain, rib/sternum : heart and lungs, vert: spinal cord

Question 4

axial skeleton is..

Answer 4

skull, vertebral coloumn and rib cage “long axis”

Question 5

appendicular skeleton is..

Answer 5

pectoral girdle, pelvic girdle, limbs,

locomotion and manipulation of environment

Question 6

4 types of bones

Answer 6

long, short, flat, irregular

Question 7

short bone ex

Answer 7

wrist and ankle bones - cubes

Question 8

flat bone ex

Answer 8

skull, scapulae, sternum, ribs

- curved

Question 9

long bone ex

Answer 9

all limb bones except girdles and wrist/ ankle and patella

Question 10

spongy bone aka

Answer 10

trabecular bone

• honeycomb of needle like projections
• in adults adipose collects in space of honeycomb

Question 11

osteoblasts

Answer 11

blasts build and produce and secrete collagen

initiates calcification process

Question 12

osteocytes

Answer 12

mature bone cells responsible for maintannecne

Question 13

osteoclasts

Answer 13

break down the bone

huge cells created from fusion of 50+ monocytes (baby macrophages)

Question 14

where are osteoclasts concentrated?

Answer 14

endosteum

Question 15

what bone cell has a ruffled border?

Answer 15

osteoclasts when they are close to bone surface so they can increase SA and secrete digestive enzymes

Question 16

osteoclasts destroy bone via…

Answer 16

digestive enzymes and pump out H+ to create acidic environment

Question 17

what is bone matrix made up mostly of

Answer 17

calcium phosphate and calcium hydroxide

Question 18

bone matrix salts combine to make___

Answer 18

hydroxyapatite which contains some F, Na, and Mg

Question 19

how is bone matrix laid down?

Answer 19

collagen fragments in segments and in gaps

Question 20

in kids __ marrow might be in long bones

Answer 20

red

Question 21

in adults long bones have ___

Answer 21

yellow marrow

Question 22

where do adults have red marrow?

Answer 22

axial skeleton, girdles (pectoral and pelvic) proximal head of humerus and femur

Question 23

what is outer periosteum made from?

Answer 23

fibrous, dense irregular CT

Question 24

___ is how blood vessels enter the shaft of a bone

Answer 24

via nutrient foramen

Question 25

periosteum covers whole bone except___

Answer 25

joint surfaces

Question 26

endosteum

Answer 26

delicate CT membrane that covers internal bone surfaces

Question 27

endosteum

Answer 27

delicate CT membrane that covers internal bone surfaces

Question 28

___ contains both osteoblasts and clasts

Answer 28

endosteum

Question 29

what do short, irregular and flat bones NOT have

Answer 29

diaphysis, epiphysis or medullary cavity

Question 30

osteons aka

Answer 30

haversian systems

Question 31

what passes through haversian canal?

Answer 31

veins, arteries, nervs lymphatics

Question 32

concentric tubes called ___ surround the hav. canal

Answer 32

lamella

Question 33

lacuna are

Answer 33

at the junctions of lamella and where spider shaped osteocytes live

Question 34

Volkmann canals are__

Answer 34

run perpendicular to the haversian canals bringing blood and nerve supply from periosteum to haversian canals onto the marrow cavity

Question 35

canaliculi allows ___ to excahange nutrients, wastes, and chem signals via ____

Answer 35

osteocytes

gap junctions

Question 36

T/F spongy bone has haversian systems

Answer 36

F

Question 37

T/F spongy bone has osteons?

Answer 37

F (same as haversian system)

Question 38

trabeculae bone has ___arranged ___ and osteocytes connected by ____

Answer 38

irregulary arranged lamella

canallici

Question 39

How does spongy bone get its blood supply?

Answer 39

if its filled with red marrow then from red marrow

If filled with yellow marrow then from Volkmanns channels

Question 40

when does bone replacement start in utero

Answer 40

after 8 wks

Question 41

intramembranous ossification is development of bone from ___

Answer 41

fibrous membranes (mesenchyme)and cartilage

Question 42

endochondral ossification is the replacement of ___ with bone

Answer 42

hyaline cartilage

Question 43

where does intramembraneous ossification occur?

Answer 43

skull, face, mandible, clavicle, pelvis, scap

Question 44

4 steps of intramembraneous

Answer 44

1. creation of ossification center
2. creation of bone maintenance mechanism
3. vascularization
4. maturation

Question 45

how long does callus formation take?

Answer 45

6-8 wks

Question 46

what vitamins do you need for bones?

Answer 46

A B12 CD, K

Question 47

what hormone is responsible for calcium and phosphate absorption

Answer 47

calcitriol

Question 48

GH and thyroxine ___ bone growth

Answer 48

stimulate

Question 49

calcitonin is released in response to ___ and causes ___

Answer 49

high calcium levels and causes decreased clast activity and increased blast activity

bottom line: builds up bone

Question 50

parathyroid hormone is released in response to ___ and causes ___

Answer 50

low blood calcium and BINDS to blasts to lower activity
blasts release osteoclast stim factor = boosts clasts

Bottom line PTH breaks bone down

Question 51

osteomalacia possible cause

Answer 51

poor nurtrition / low calcium levels

Osteoid is produced by inadequately mineralized

Question 52

Rickest is

Answer 52

osteomalacia in kids: bowed legs, deformities of pelvis ribs skull etc

Question 53

typically osteomyelitis is ___

Answer 53

infection primary to bone

Question 54

what is RF for osteomyelitis

Answer 54

IV drug use

Question 55

common fx related to osteoporosis

Answer 55

compression fx vertebrae, femur, colles radial and distal ulna