L1

Question 1

High LET vs Low LET damgage

Answer 1

High (alpha): direct damage 33%

Low (x, gamma) : indirect thru ionizing water–>free radicals 67%

Question 2

Mitotic delay

Answer 2

G1 arret

G2 block

Question 3

Law of Bergonie and Tribondeau

Answer 3

Cell tend to be radiosensitive if

• high division rate
• long dividing future
• unspecialized

Question 4

High radiosensitivity

Answer 4

Lymphocytes
Bone marrow
Testes
Intestines
Mucous membranes

Question 5

Low radiosensitivity

Answer 5

Optic lens
Mature blood cells
Muscles
Neurons

Question 6

Acute effects begin around ____ rad

Answer 6

200 rad

Question 7

1 Gray = ___ Rad

Answer 7

1 Gy=100 rad

Question 8

Stochastic probability and severity and threshold

Answer 8

Probability increases with dose but severity does not

No threshold

Question 9

In utero low dose radiation

Answer 9

NOT GENETIC…baby being exposed while in uterus

Question 10

Genetic mutation threshold

Answer 10

No threshold

Question 11

Genetic doubling dose

Answer 11

2Sv
2 Gray
200 rad

Question 12

Genetic doubling dose definition

Answer 12

Amount of radiation to produce in the next generation as many additional mutations as would arise spontaneously

Question 13

Do

What is it

Answer 13

Determines the slope of the straight portion of survival curve
Radiation required to reduce cells to 37% (.1 to .37)

Question 14

Effect of oxygen

Answer 14

cells die faster in presence of oxygen

Question 15

Statistical confidence for cancer

Answer 15

100msv

Question 16

Linear No Threshold

Answer 16

We only know what happens at high doses and extrapolate to zero..There is no safe dose

Question 17

Uterine exposure times and effects

Answer 17

0-1 weeks: death
2-7: developmental, growth, cancer
8-40: same but less chance

Question 18

Most important determinant of radiogenic risk for cancer

Answer 18

Age