Radiation biology Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Exposure:

  1. Define.
  2. Units?
A
  1. The ability of XRs to ionize air. It is the concentration, in air, of radiation at a specific point.
  2. Roentgens.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Absorbed dose:

  1. Define.
  2. Units?
  3. How many rads in this unit?
A
  1. Amount of energy absorbed per unit mass.
  2. Grays or rads
  3. 1 Gy = 100 rads.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Rads, Grays, Sieverts

  1. # rads / Gy?
  2. SI defn Gray
  3. What do Sieverts measure?
  4. How many rems in 1 Sv?
A
  1. 100 rads/Gy
  2. 1 Gy = 1 joule/kg (hence, Gy is defined as amt of energy absorbed per unit mass)
  3. Health/biologic effect of ionizing radiation.
  4. 1 Sv = 100rem.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Equivalent dose:

  1. Define.
  2. Units?
  3. Weighting factors for: photons (XRs, gamma rays), neutrons, alpha particles.
A
  1. Radiation dose to tissue based on the type of radiation.
  2. Sieverts, as it measures health effect (or rem).
  3. Photons: 1; neutrons = 5-20; alpha particles = 20.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Effective dose

  1. Define.
  2. Units
  3. Equation
  4. What is the value if all the radiation is absorbed (1 Gy, say)?
  5. Give tissue weighting factors for the most & least sensitive tissues.
A
  1. Takes into account whether radn has been absorbed by the specific tissue.
  2. Sv.
  3. dose x radn weighting factor x tissue weighting factor, so essentially this is EqD x tissue weighting factor.
  4. If 1 Gy absorbed, then 1 Sv.
  • Most: 0.12; bone marrow, colon, lung, breasts, stomach.
  • Least: 0.01; bone, skin, brain.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q
  • Draw the table of exposure & the 3 dose types: definitions, units & other notes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the risk of developing a fatal cancer with 1 Sv radn?

A

5.5% chance.

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

Radn dose (Gy) that causes instant cell death?

A

1,000 Gy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  1. Which clinical syndrome is most sensitive to XRs.
  2. Which is most sensitive to UV radn?
A
  1. Ataxia telangiectasia.
  2. Xeroderma pigmentosa. (mnemonic: dermis gets pigmented by UV)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  1. What is the dose for a CTAP?
  2. What is a dose that makes you sick?
  3. What total body dose will cause nausea 30% of the time?
A
  1. 30 mGy.
  2. Gy, e.g., 2 Gy messes w/your bone marrow.
  3. 0.75-1.25 Gy.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly