Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

SF3: Cardiovascular, Respiratory and Musculoskeletal Systems > W2 Bone Physiology > Flashcards

W2 Bone Physiology Flashcards

1
Q

what are the five basic functions of the skeleton?

A

framework and levers
protection
mineral storage
fat storage
production of blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

bone is a rigid form of what?

A

connective tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the basic unit of bone?

A

an osteon (as part of the Haversian system)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

collagen type 1 scaffold makes up about what % by weight of bone?

A

15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

the organic matrix makes up which percentage?

A

10% by weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the major mineral component of bone?

A

hydroxyapatite (CaPO4(H2O)6)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what does an osteogenic cell develop into (that maintains bone tissue)?

A

osteogenic cell into and osteoblast into and osteocyte

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

describe where the principal bone cell, osteocytes, are found:

A

found in small spaces in the mineralised matrix called lacunae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what connects adjacent lacunae?

A

small canals termed canaliculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what do osteocytes surround?

A

haversian canals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

is bone matrix impermeable or permeable to nutrients?

A

impermeable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what do osteocytes communicate through?

A

gap junctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what makes up the bone cell layer?

A

periosteum, endosteum and haversian canals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

where is bone fluid found?

A

between bone cell layer and bone substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what do osteoblasts do?

A

synthesise and secrete collagen and other components of the cell matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is osteoid?

A

a tissue that undergoes calcification and is deposited as lamellae or layers in the bone matrix, create the foundation of bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

calcium phosphate crystals are formed by what?

A

osteoblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what do osteoclasts do?

A

they destroy bone matrix by acidifying their subcellular space to dissolve CaPO4 and enzymatically digest collagen and other matrix proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are osteoclasts derived from?

A

haemopoietic lineage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

are osteoclasts multinucleated?

A

yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

osteoclasts have the capacity to spread over how many microns?

A

200

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what happens to the end products of degradation of osteoclasts?

A

they are absorbed into the osteoclasts before being released into the interstitial fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

as osteoclasts reabsorb bone, they leave behind what to encourage osteoblasts to mature?

A

mitogens (growth factors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

osteoclasts remove damaged matrix to avoid catastrophic failure allowing what?

A

repair!

25
Q

to achieve constant mass of bone, what must be equal?

A

the amount of bone being formed must be equal to the amount of bone being removed

26
Q

what is dense bones (osteopetrosis) caused by?

A

too much activity from osteoblasts

27
Q

what causes osteoperosis?

A

too much osteoclast activity

28
Q

nutrient arteries of bones enter through what?

A

a nutrient foramen (opening)

29
Q

which part of the bone does the nutrient artery supply?

A

the inner 2/3 of the bone from the endosteum

30
Q

what supplies the outer third of the bone?

A

periosteal vessels via attachments of muscles and tendons

31
Q

describe the endosteal side of bone:

A

woven or cancellous bone housing the bone marrow, the blood supply runs parallel to the long axis in cortical bone inside Volkmanns canals

32
Q

describe the periosteal side of bone:

A

outer bone surface, also brings blood supply to the bone via soft tissue attachments

33
Q

where does ossification start in long bones?

A

starts in the middle

34
Q

the bone collar forms in the connective tissue, what does the outer layer of this eventually become?

A

vascularised periosteum

35
Q

describe the first three steps of endochondral ossification:

A
  1. bones develop from structures of hyaline cartilage (which is lined with a connective tissue sheath - perichondrium)
  2. ossification begins in the middle of long bones with the growth of blood vessels into the perichondrium (periosteum)
  3. outer periosteum layer has dense, fibrous connective tissue, the inner layer is made up of osteoprogenitor cells. the vascularisation provides nourishment to these cells, stimulating them to differentiate to osteoblasts
36
Q

describe steps four and five of the ossification process:

A
  1. the osteoblasts begin to produce osteoid, which becomes ossified and forms the bone collar
  2. the bone cavity is then formed in the centre of long bones (occurs via hypertrophic chondrocytes releasing alkaline phosphatase, increasing P in the cartilage matrix) this then precipitates calcium phosphate crystals = calcification
37
Q

describe the final two steps of ossification:

A
  1. blood vessels then infiltrate the centre of the calcified matrix allowing osteoclasts and osteoprogenitor cells to migrate along them, the calcified cartilage matrix is then gradually replaced by bone
  2. ossification then progresses towards the ends of long bone, as osteoclasts break down tissue in the middle of the bone to form the marrow cavity
38
Q

ossification spreading from the primary centre (middle) gradually approaches what?

A

ossification spreading from secondary centres (i.e. epiphyseal growth plates)

39
Q

longitudinal growth occurs via what?

A

growth plates

40
Q

what does appositional growth allow?

A

the bone to become thicker

41
Q

what are the five zones of a growth plate?

A
  1. resting/reserve
  2. proliferation
  3. hypertrophy/calcification
  4. cartilage erosion
  5. endochondral ossification
42
Q

where would you find the resting/reserve zone?

A

at the epiphyseal end

43
Q

what occurs in the proliferation zone?

A

chondrocytes form and multiply

44
Q

what happens to chondrocytes in the zone of hypertrophy/calcification?

A

they become bigger and the matrix begins to multiply

45
Q

what occurs in the zone of cartilage erosion?

A

the matrix is removed by chondroclasts and blood vessels invade

46
Q

what occurs in the zone of endochondral ossification?

A

bone replaces the removed cartilage and bone elongation occurs

47
Q

what defines the adult height of an individual?

A

growth plate closure or healing defines skeletal mature length

48
Q

roughly at what age are toy breeds skeletally mature?

A

8 months old

49
Q

roughly at what age are large/giant breeds skeletally mature?

A

14 months old

50
Q

how long does it take for cats to stop growing?

A

20-24 months

51
Q

what is intramembranous ossification?

A

when osteoblasts make bone directly within a membranous fibrous tissue structure, there are two layers that form bone between them to form two parallel plates of bone that become the to cortices of the flat bones

52
Q

skull bones and pelvic and scapular structures form in which way?

A

intramembranous ossification

53
Q

what forms an ossification?

A

selected centrally located mesenchymal cells cluster and differentiate into osteoblasts, forming an ossification centre

54
Q

what happens after an ossification centre appears in the fibrous connective tissue?

A

bone matrix (osteoid) is secreted within the fibrous membrane, osteoblasts begin to secrete osteoid which is mineralised within a few days (trapped osteoblasts become osteocytes)

55
Q

between which membranes does bone form in intramembranous ossification?

A

two periosteal membranes

56
Q

does intramembranous ossification have a cartilaginous precursor structure?

A

no

57
Q

what is wolffs law?

A

the idea that bone will adapt to the loads placed upon it

58
Q

what effect does the largest applied forces have on bone?

A

trabecular struts or plates will form in orientation with the largest applied forces

SF3: Cardiovascular, Respiratory and Musculoskeletal Systems (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions