Brainscape's Knowledge GenomeTM

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


See full index

year 2 lcrs anatomy limbs > 1: Bone > Flashcards

1: Bone Flashcards

1
Q

What are the main functions of the bone?

A
  • Structural support (shape+muscle action)
  • protection
  • blood formation
  • mineral storage site
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the two mechanical properies of bone?

A
  1. Cable-like flexibility –>osteioid due to collagen fibres (resistant to tension)
  2. Pillar-like stiffness –> impregnation of collagen with hytroxyapatite –> complex calcium hydrophosphate (also causes resistance to compression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the structure of immature or healing bone?

A

Woven bone

–> quite irregular structure, not as stable

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

What is the normal structure of a bone in healthy adults?

A

Mature bone: Lamellar bone –>

organised and stable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain the different arrangements of lamellar bone

A

Arranges into

  1. Cortical bone (hard, outer part), compact lamellar bone
  2. Cancellous bone (spongy/ trabecular bone)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is an osteon?

How is it organised

A

Small funtion al unit of bone–> organised as laminar organised cells around a centric canal that carries blood vessels

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

How does the organisation of spongey osteons differ from compact bone osteons?

A

They barely differ and have the same structure –> both Lamellar

but spongy part might be a bit smaller

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

Explain the structure of an osteocyte

A

It is a big cell with many connections to other cells (gap juctions) to share nutrients

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

Summarise the bony blood supply

A

A nutrient artery (middle part, but also epyphisis artery and veins) enters the bone through a nutrient canal

Bone is highly vascularised

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

How do you call the most outer part iof bone?

What is its function?

A

It is the periosteum

  • Vascularised
  • –> important in growth and repair
  • good sensory supply (hurts when fractures)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Explain the developemnt of osteocytes

A

Develop from osteoblasts (that develop from osteogenic cell)

17
Q

When do bones start to form?

When do they stop growing?

A

The skeleton starts to form at 6 weeks

Stops growing at Age 25

18
Q

What are the two types of bone development?

A
  1. Intramembranous –> in existing vascular connective tissue
  2. Endochondral –> exisiting fetal cartilage models
19
Q

Explain intramembranous formation of bone

A
  • In existing vascular connective tissue
  • Bone matrix (ostein) deposited around collagen
  • Mineralises to form woven bone
  • Remodels to lamellar bone

–> normally in flat bones

20
Q

How does bone growth?

A

When bone growth it still needs to carry weight –> not ideal if that is the end of the bone

So:

  • Shaft ossifies first, followed by epiphyses
  • Growth continues by ossification at growing cartilage plate between them
  • Growth cessation when cartilage growth ceases and plate is over-run by ossification
21
Q

Explain endochrondal bone growht

A

Forms around existing fetal cartilage models

  • Cartilage calcifies and chondrocytes (part of cartilage) die
  • Periosteal osteoclasts cut channels for sprouting vessels
  • Osteoblasts enter with vessels to build bone around them
22
Q

Explain the structure and function of the epiphysal plate

A

It is a cartilage region between shaft and head of bone

–> Cartilage forms and gets ostefied (endochondral) –> enables bone growth

23
Q

What happens to bone when it is used little and a lot?

A

Increases or decreases bulk and density in response to pattern of use

  • But: when less used: loss of bone mass (ISS)
24
Q

What shows that bone is an adaptable structure?

A
  • Can grow
  • changes density with use
  • can remoddel depending on pattern of use
  • ability to repair
25
Q

What is the role in osteocytes in bone repair?

A

•Osteocytes maintain matrix but can activate osteoblasts for new bone building

26
Q

How does bone grows in diameter?

When does this happens?

A

Periosteum is activated to become osteoblasts

27
Q

Expalint the process of bone healing

A
  1. Haematoma
    • becomes infiltrated by fibrous matrix and invaded by cartilage/bone progenitors
  2. Blood vessels invade damaged structure
  3. Woven bone is forming
  4. Remoddeling in lamellar bone
28
Q

What happens to the bone at high calcium levels?

A

Calcitonin released by parafollicular thyroid cells;

  1. Inhibition of breakdown of bone matrix by osteoclasts
  2. Promotion of Ca2+ uptake into bone matrix
29
Q

What happens to bone at low Ca2+ levels?

A

Parathyroid Hormone (PTH) released

  • Promote osteoclast bone resorption
  • increases Ca2+ re-absorption by the kidneys + intestine

year 2 lcrs anatomy limbs (15 decks)

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