Brainscape's Knowledge GenomeTM

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


See full index

Musculoskeletal > Bone: structure growth and repair > Flashcards

Bone: structure growth and repair Flashcards

1
Q

Compact bone

A

Around the outsides of bone.

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

Coarse cancellous bone

A

Adult spongy bone

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

Fine Cancellous bone

A

Fetal bone. Cancellous means spongy.

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

Trabeculae

A

Small elements in lamaller bone (adult coarse cancellous or stingy bone)

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

Why is bone good under tension

A

It contains a lot of collagen

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

Why is bone good under pressure and torsion

A

Hydroxapatite

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

Components of bone

A

Collagen and hydoxyapatite. Very little proteoglycan

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

Periosteum

A

Fibrous layer on the surface of bone that contains osteoblasts that generate new bone

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

Endosteum

A

Surface of cancellous bone and inner surface of compact bone with similar properties to the periosteum

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

Cells in bone

A

Osteoblast (immature)

Osteocyte (mature)

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

Fibre(s) in bone

A

Collagen

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

Proteoglycan matrix in bone

A

Decorin

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

What does decor do

A

Holds the collagen fibres together

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

Glycoproteins in bone

A

Osteonectin (bind components of matrix together)

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

What is the mineral in bone

A

Hydroxyapatite. Allows the bone to withstand compression and torsion

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

Describe membrane bone

A

A kind of fine cancellous (fetal bone). Forms from osteoblasts in flat sheets creating the flat bones of the skull

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

Describe cartilage bone

A

A kind of fine cancellous bone (fetal bone) formed from cartilage creates most bones in the body.

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

Describe woven bone

A

Fetal fine cancellous bone. Called woven as the collagen fibres are not yet arranged in parallel.

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

How does fine cancellous bone (woven bone) turn into adult bone (lamellar bone)

A

Turns into coarse cancellous (spongy) and compact bone. It becomes lamellar bone when collagen fibres are laid down in alternating parallel sheets. Happens gradually.

20
Q

Where are osteoblasts found

A

On the surfaces of bone in the osteogenic layers, either periosteum or the endosteum

21
Q

How is the periosteum attached to the bone

A

Through collagen fibres at right angles to the bone known as sharpy’s fibres

22
Q

Describe the growth of bone

A

Grows at the periosteal and endosteal surfaces. Osteoblasts divide and the progeny away from the bone surface remains in the periosteum or endosteum and divide again. The other progeny secretes new bone matrix. Called appositional growth

23
Q

Appositional growth

A

Means applying something (bone) to a surface

24
Q

When do osteoblasts become osteocytes

A

Once they divide and secrete matrix and have surrounded themselves with hydroxyapatite

25
Q

What do osteoblasts secrete

A

Collagen fibres and hydroxyapatite and other matrix components

26
Q

How do osteocytes obtain their nutrition

A

Osteocytes have cell processes which run in small channels called canaliculi. Each cells passes on nutrients to its neighbour which in turn passes its nutrients to its neighbour. Nutrition comes from the endosteum or periosteum

27
Q

How far can nutrients be passed before the last cell in the chain suffers from deprivation

A

0.2 mm. Therefore maximum thickness of trabeculea is 0.4mm (pass from both surface). This is why blood supply has to exist in compact bone which is thicker than 0.4 mm

28
Q

How do blood vessels get inside the bone?

A
  1. They are enclosed at the surface during appositional growth (primary)
    2) They invade channels in bone formed by osteoclasts (secondary)
29
Q

Two forms of osteon formation

A

Primary (appostional) formation where periosteum surrounds blood vessels and becomes endosteum which lays down bone in towards blood vessel.
Secondary

30
Q

What is the canal in the middle of the osteon called

A

Havasian canal

31
Q

What are the canal the run perpendicular to the osteon that hols capillaries that feed into the havarsian canals called

A

Volkmans canals

32
Q

What are the canal the run perpendicular to the osteon that hols capillaries that feed into the havarsian canals called

A

Volkmans canals

33
Q

How does bone remodelling occur?

A

Through removing bone from the inside and adding bone on the outside.
This occurs through osteoclasts derived from blood cells.

34
Q

How do osteoclasts work

A

Osteoclast seals onto bone with ‘collar’. In the basolateral membrane of the osteoclast is a ruffled border. Within the border are vesicles holding acids and enzymes. Acids digest hyroxapatite, enzymes digest the collagen.

35
Q

Hormonal control of bone removal

A

Parathyroid hormone- increases osteoblast and osteoclast activity, decreases bone mass.
Calcitonin- reduces osteoclast activity

36
Q

Describe the interplay between RANK and RANK-L

A

RANK is a molecule found on primitive osteoclasts. RANK-L is found on mature osteoblast. When RANK-L binds to RANK this signals the primitive osteoclast to differentiate and become mature.

37
Q

What does OPG do

A

OPG- osteoprotegrin. Acts to block RANK-L binding to RANK. Inhibits bone loss

38
Q

Why does decreasing oestrogen levels cause osteoperosis

A

Oestrogen reduces the activity of osteoclasts through decreasing RANK L levels

39
Q

What does HRT do

A

Reduces the activity of osteoclasts, less bone reabsorption

40
Q

Is most adult bone composed of primary or secondary osteons?

A

Secondary

41
Q

At what rate is bone replaces each year?

A

2%

42
Q

What are the three molecules that control osteoclast activity

A

RANK, RANK-L and OPG

43
Q

Where does growth in long bones occur

A

Epiphyseal plates

44
Q

Describe the process of long bones growing in length

A

In youth there are epiphyseal plates which grow cartilage at one end which at the other end the cartilidge dies and blood vessels bring in osteoblasts and bone forms this occurs until closure of the epiphyseal plates during/ after puberty.

45
Q

How do bone fractures heal

A

The periosteum and endosteum provide osteoblasts which secrete bone cells in a collar around the fracture site. Later osteoclasts dig out channels and new secondary osteons to knit together fracture

46
Q

What are the stages of growth in growth in length of a long bone

A 
From the epiphyses side of cartilage:
Zone of resting 
Zone of proliferation
Zone of maturation
Zone of ossification
47
Q

What is a howships lacunae

A

The space around the osteoclast on the surface of the bone.

Musculoskeletal (22 decks)

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