Bone Quiz 1/2 (Development and on is quiz 2) Flashcards

1
Q

Bone compostion

A
  • organic component
  • inorganic component
  • all bones, regardless of shape have the same composition
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

organic component of bones

A
  • mineralized
  • 25% of dry weight
  • tensile strength (tension, torsional)
  • allows bones to bend a bit without snapping
  • osteoid (collagen) primary component
  • cells and fibers
  • cells secondary component:
  • osteoblasts- bone forming, lays down osteoid
  • osteocytes- maintenance
  • osteoclasts- resorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

osteocytes

A
  • become trapped in the bone matrix (lacunae)

- maintain bone health

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

osteoclasts

A
  • removes bones so it can be replaced
  • important for bone health
  • so it doesnt become brittle
  • macrophages
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

inorganic component of bone

A
  • 65% of dry weight
  • ground substance
  • compressional strength- thick, strong
  • calcium primary component
  • crystalline structure
  • hydroxyapatite crystals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

if 65% of bone weight is inorganic ground substance and 25% includes fibers and cells, what does the other 10% represent

A
  • water
  • fluid
  • fibers
  • cells
  • ground substance
  • bone is connective tissue
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

organic component: cells

A

-osteoregenerator
form osteoblast
-osteocyte forms after being trapped in lacunae
-osteoclast

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

organic component: osteoid

A
  • before it is mineralized
  • collagen fibers
  • mineralization occurs between the collagen fibers and takes the crystalline structure form
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

inorganic component: crystalline structure

A
  • after mineralization
  • crystalline structure
  • hydroxyapatite crystals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

bone is dynamic

A
  • responds to growth and sex hormones (growth)
  • responds to fracture (healing)
  • responds to plasma calcium levels (Ca homeostasis)
  • responds to stress (modeling and remodeling)
  • it is able to be so dynamic bc it is dynamic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

bone structure

A
  • structural support for the rest of the body
  • a substrate to act upon: movement, breathing
  • space for hemopoiesis- blood cell formation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

which of the following bones serve to protect thorax organs like the lungs

A
  • ribs

- sternal

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

bone protection

A
  • skull: brain, sense organs..
  • ribcage: thorax organs
  • pelvis: pelvic organs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

hemopoiesis

A
  • formation of blood cellular components
  • stem cells within RED marrow can differentiate into many cell types
  • erythrocytes- RBC
  • leukocytes- WBC
  • osteoclasts- bone resorbing cells (macrophages)
  • YELLOW marrow is mostly a site of fat storage
  • red marrow is found in cancellous portions of flat bones, vertebral bodies, and long bone epiphyses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Calcium homeostasis

A
  • Ca is necessary for many biological functions
  • hormone synthesis
  • motor nerve function
  • muscle contraction
  • bone is the major reservoir of calcium
  • low circulating calcium levels will trigger bone resorption to release calcium
  • low plasma Ca level: parathyroid releases parathyroid hormone -> produces osteoclasts
  • high plasma Ca level: thyroid releases calcitonin -> produces osteoblasts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

structural failure

A
  • fractures
  • joint reconstruction
  • disorders/diseases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

fractures

A

-millions of fractures per year in the US with 5-10% represnetion difficult fractures

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

joint reconstruction

A
  • 250,000 hip replacement per year

- 300,000 knee replacement per year

19
Q

disorders/diseases-

A
  • related to serum minerals (calcemias, parathyroidis,. thyroidism)
  • abnormal bone remodeling (osteoporosis, osteopetrosis)
  • genetic/developmental
  • extracellular calcification
20
Q

osteoporosis

A
  • high osteoclast activity
  • low bone density- amount of matter per cm
  • reduce resorption rate by exercise
  • fracturally greater resorption than formation
21
Q

osteopetrosis

A
  • no osteoclast activity
  • thick walls of the bone
  • thinner cavity
  • albers-schonberg disease: neurological complications, clotting issues, increased incidence of fracture
22
Q

osteopetrosis might result from lack of hormone production from which structure

A

parathyroid

23
Q

macroscopic structure

A
  • cortical (compact) bone- high density and strength, found at outer surface
  • cancellous (spongy) bone- network of bone that transmits stressed to cortical bone (epiphyses and center of bones)
24
Q

cancellous (spongy) bone

A
  • transmits forces to the cortical bone
  • absorbs shock
  • deform without breaking easily
  • network of bone that transmits stressed to cortical bone (epiphyses and center of bones)
25
Q

epiphysis

A

ends of long bone

  • cancellous and cortical bone
  • formed from secondary ossification center
26
Q

diaphysis

A
  • midshaft of a long bone
  • cortical bone
  • formed from primary ossification center
27
Q

metaphysis

A

-location of fused growth plate between epiphysis and diaphysis

28
Q

haversian canal

A

-central canal of the osteon with blood vessels and nerves

29
Q

osteon

A
  • circular layers of bone surrounding central canal
  • layed down by osteoblasts
  • circle of bone with osteocyte in the middle
30
Q

perisoteum

A
  • superficial fibrous layer and site of bone formation
  • outer layer
  • fibrous connective tissue and bone forming cells
  • lamina are layed down to increase radius
31
Q

lacunae

A
  • osteocyte locations between bone layers

- osteocytes are trapped here

32
Q

canaliculi

A

-little canals that contain osteocyte dendrites

33
Q

cancellous (spongy) bone

A
  • organic and inorganic
  • collagen fibers
  • calcium hydroxyapetite
  • layers of lamellae
  • form thinner trabeculae network
  • without osteons
34
Q

development of bone

A
  • intramembranous ossification

- endochondral ossification

35
Q

intramembranous ossification

A
  • mesenchymal cells to bone
  • no cartilage intermediate
  • mesenchymal differentiate into osteoblasts -> form osteons
  • woven bone -> remodeled
36
Q

endochondral ossification

A
  • go from compact cells that differentiate into cartilage which is then replaced by bone
  • more common
  • mesenchymal differentiate into chondrobalsts
  • cartilage forms at the center
  • perichondrium
  • chondroblasts get trapped and become chondrocytes
  • chondrocytes go through hypoxia -> call on oxygen
  • chondroclasts come and remove cartilage -> replaced by bone by osteoblasts
  • primary ossification center- diaphysis
  • secondary ossification center- ossification in epiphysis
37
Q

mesenchymal cells

A
  • cartilage and bone cell progenitors
  • migratory
  • can differentiate into many different things
  • form within compact regions
38
Q

periosteal apposition growth

A
  • bone diameter increases through bone deposition at the periosteum
  • intramembranous
  • thickness of cortical bone typically stays the same through equal resorption and growth
  • radial expansion of long bone is intramembranous although longitudinal growth is endochondral
39
Q

endochondral growth ex

A
  • site of bone length increase

- fracture healing

40
Q

Which part of long bone represents the location of growth plate fusion

A

-metaphysis

41
Q

remodeling

A
  • sequential resorption of bone by osteoclasts and replacement by osteoblasts
  • resorption and replacement at the exact same site of the bone
  • can be in response to:
    1. hormones (loss of estrogen during menopause)
    2. low plasma Ca levels (Ca homeostasis)
    3. microdamage caused by physical stress
    4. mechanical disuse (bone loss)
42
Q

microdamage

A
  • can damage the osteocyte
  • picked up by the dendrites
  • call osteoclasts to the site
  • forms a new osteon
  • remodeling
43
Q

wolffs law: remodeling

A
  • structural organization of bone reflects its function
  • tends to form more bone in high stress areas
  • structural organization of bone reflects its function
  • trabeculae forms parallel to direction of greatest mechanical loads
  • trabeculae oriented to directions of stresses (loads)
  • repeated activity of high stress can cause increase in bone mass
  • ex. tennis player dominant arm bone will have higher bone mass/density
44
Q

mechanical disuse

A
  • ex. astronauts- 1-2% of bone mass is lost per month of space flight
  • you need some level of stress to maintain healthy bone