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Flashcards in chap 6 bone and skeletal Deck (82):
1

what is the composition of the skeletal system?

bones
joints with cartilage, tendons, and ligaments

2

what does a ligament connect?

bone to bone

3

what does a tendon connect?

bone to muscle

4

what are the 3 types of cartilage?

hyaline
elastic
fibrocartillage

5

hyaline

provides firm support with some flexibility

6

where is hyaline cartilage found

articulate cartilage at ends of bones
costal cartilages
respiratory tract, voice box, nasal

7

elastic cartilage

stretch flexibility

8

where is elastic cartilage found?

ears
epiglottis

9

fibrocartillage

strength from collagen fibers but cushioning ability as well
very thick fibers

10

where is fibrocartillage found?

knee cartilage
vertebrae discs

11

pad like cartilage of the knee

menisci

12

functions of bone

support
movement
protection
mineral storage
blood cell formation

13

classifications of long bone

long bones
short bones
flat bones
irregular bones

14

long bones

functions as levers
ex. humerus

15

short bones

roughly cube shaped
glide motion
ex. ankle and wrist bones

16

flat bones

functions as protection
ex. skull, ribs, sternum

17

irregular bones

things fit into these irregularities
ex hips vertebrae

18

bone tissue types

compact
spongy

19

compact bone

smooth and solid in appearance
outer casings
tougher
more minerals

20

spongy bones

honeycomb
spaces help diffuse force

21

structure of long bones

diaphysis
epiphysis
blood vessels
medullary cavity
membranes

22

diaphysis

shaft of bone

23

epiphysis

expanded end area

24

why do bones broaden?

to relieve stress

25

epiphyseal line

will eventually become a line
growth plate used to elongate bone

26

red marrow

blood cell production
eventually becomes yellow and stops producing

27

articulate cartilage

cushioning

28

medullary cavity

contains bone marrow

29

membranes

used to make bones
periosteum
endosteum

30

periosteum

outside of bones
contains sharpeys fibers

31

perforating (sharpeys) fibers

more concentrated at tendon and ligament

32

endosteum

internal of bone

33

structure of short, flat, and irregular bones

sandwhich - thin outside compact layers with spongy in between

34

what do bone cells excrete?

extracellular matrix
responsible for maintaining and remodeling

35

bone cells

osteogenics
osteoblasts
osteocytes
osteoclasts

36

osteoblasts

bone forming
deposit bone matrix

37

ossification

build up bone matrix

38

functions of bone matrix

synthesize collagen
accumulate calcium and phosphate

39

appositional growth

osteoblasts of the inner periosteum add a new layer to the preexisting bone
increasing diameter

40

osteocytes

mature bone cells trapped in the new matrix

41

function of osteocytes

maintain existing matrix

42

osteoclasts

bone destroying cells
clast means dissolve

43

what is the function of osteoclasts

responsible for the breakdown and reabsorption of bone matrix, constantly occuring
secrete H+ and enzyhmes to breakdown mineralized bone matrix
calcium and phosphate freed

44

how are osteoclasts formed?

fusion of stem cells

45

structures of compact bone

osteon
circumferential lamellae

46

structure of osteon

lamella
central canal
perforating canals
canliculi
osteocytes

47

lamella

ring around osteon

48

central canal

blood vessels and nerves

49

perforating canals

connect vessels and nerves

50

canaliculi

the space between two osteocytes

51

circumferential lamellae

go around bone as whole, outside rings
used for bone widening

52

spongy bone

less dense, lighter
consists of trabeculae with spaces in between

53

trabeculae

interconnecting plates found in spongy bone

54

chemical composition of bone matrix

flexibility (collagen) + strength (minerals)

55

how do flat bones of the skull grow?

intramembranous
grow from inside point outward
ex. fontanels

56

intramembranous

calcification centers develop within a membrane

57

what happens to fontanels?

turn into sutures after growth stops

58

model for long bone growth

bones shape is formed by hyaline cartillage
osteocytes replace chondrocytes and cartillage bone
active growth areas of cartillage remain in the epiphyses forming growth plate through adolescence

59

what age does epiphyseal line form?

18 yrs for female
21 yrs for male

60

factors affecting bone growth

nutrition
hormones

61

nutrition that affect bone growth

vitamin D
calcium
vitamin C

62

vitamin D deficiencies

rickets
osteomalacia

63

rickets

childhood demineralization of bone
formative deformities

64

osteomalacia

adult form softening of bone

65

calcium is dependent on what?

vitamin D absorption

66

vitamin C deficiencies

scurvy - lack of normal collagen synthesis
wound healing impaired, loose teeth
impacts fibrosis stage of repair

67

hormones that impact bone growth and remodeling

growth hormone
thyroid hormone
sex hormones

68

thyroid hormone does what?

increases metabolism -> increase energy -> increase repair

69

sex hormones do what to bone growth

testerone prolongs growth at epiphyseal plates
estrogen increases bone mass

70

"a healthy bone is..."

a stressed bone

71

clasifications of fractures

closed/ simple (single)
open / compound (multiple)

72

how are bone fractures treated?

reduction (realignment of the bone)

73

types of fractures

comminuted
compression
depressed
impacted
spiral
greenstick

74

steps of bone repair

hematoma is formed
break is splintered by fibrocartillage
fibrocartillage callus is replaced by bony callus
bony callus is remodeled

75

effects of aging

highest bone mass is around 30
bones become more brittle
osteoporosis

76

why do bones become brittle as we age?

less flexible collagen is synthesized
less mineral matrix is deposited as osteoblasts slow down
women are susceptiple to demineralization after menopause

77

osteoporosis

results from the rate of absorption beaing faster than the rate of new bone formation

78

what does the female hormone estrogen do?

lessen osteoclast activity
as estrogen levels drop after menopause, some women experience rapid demineralization
women can lose up to 50% bone mass

79

causes of osteoporosis

reduction of dietary calcium
overproduction of parathyroid hormone
overactive osteoclasts

80

what is the purpose of the parathyroid hormone

causes calcium to move from bone to blood

81

treatments of osteoporosis

vit D and calcium
drugs aimed at slowing down osteoclasts
fosomax, HRT (hormone replacement therapy)

82

calcium homeostasis in the blood

very tightly controlled by the body within 10% of normal
increase by 30% will cause nervous and muscle cells to become unresponsive
decrease by 35% will cause overexcited neurons and convulsions