Deck 30: Fundamental Principles of Radiobiology

Question 1

The possible beneficial effect of a small amount of radiation is called _____.

A) radiosensitizing
B) hormesis
C) radioprotection
D) protraction

Answer 1

hormesis

Question 2

As LET _____,the RBE _____.

A) increases, remains the same
B) decreases, remains the same
C) increases, increases
D) increases, decreases

Answer 2

increases, increases

Question 3

Humans are most radiosensitive during _____.

A) fetal stages
B) infancy
C) adulthood
D) old age

Answer 3

fetal stages

Question 4

Human cells cannot recover from radiation damage after there is _____.

A) cellular repair
B) cellular repopulation
C) interphase death
D) sublethal damage

Question 5

Tissues that are _____ with a _____ metabolic rate are more radiosensitive.

A) immature, low
B) immature, high
C) mature, low
D) mature, high

Question 6

The human dose-response relationship at low ranges of radiation is calculated using _____.

A) known responses from low doses
B) extrapolation from high ranges
C) human experiments
D) all of the above

Question 7

A protracted dose of radiation is given _____.

A) over a long period of time
B) all at one short exposure
C) in a series of separate doses
D) in two large doses

Question 8

The LET of diagnostic x-rays is _____ keV/ m.

A) 0.2
B) 0.3
C) 3.0
D) 50

Question 9

The human application of radioprotective agents would _____.

A) double radiation damage
B) be fatally toxic
C) reduce radiation effects by half
D) reduce radiation effects by one fourth

Question 10

_____ is a measure of the rate that energy is transferred from ionizing radiation to soft tissue.

A) LET
B) RBE
C) MeV
D) OER

Question 11

Studies of the effects of radiation show that low doses may _____.

A) stimulate the immune system
B) extend the life span
C) stimulate hormonal responses
D) all of the above

Question 12

A _____ response to radiation is directly proportional to the dose received.

A) linear
B) nonlinear
C) curvilinear
D) non-threshold

Question 13

A dose of 10 Gy given to a patient in 5 doses of 2 Gy per day is a _____ dose.

A) protracted
B) fractionated
C) diagnostic
D) fatal

Question 14

Fractionation and protraction are used for radiation therapy because they allow the patient to _____.

A) recover between doses
B) have higher total doses
C) repair damaged tissues
D) all of the above

Question 15

If a response to radiation is expected,no matter how small the dose,then that dose-response is _____.

A) linear
B) nonlinear
C) nonthreshold
D) threshold

Question 16

The law of _____ states that the radiosensitivity of living tissue is a function of the metabolism and maturation of that tissue.

A) Watson and Crick
B) Roentgen and Plank
C) Hurter and Driffield
D) Bergonie and Tribondeau

Question 17

Tissue is _____ radiosensitive under high oxygen conditions and _____ radiosensitive under hypoxic conditions.

A) less, equally
B) less, more
C) more, less
D) more, equally

Question 18

Which dose-response relationship can follow a sigmoid curve?

A) linear-nonthreshold
B) linear-threshold
C) nonlinear-nonthreshold
D) nonlinear-threshold

Question 19

Radiation induced genetic damage follows a _____ dose-response relationship.

A) linear-nonthreshold
B) linear-threshold
C) nonlinear-nonthreshold
D) nonlinear-threshold

Question 20

The RBE of diagnostic x-rays is equal to _____.

A) 20
B) 10
C) 5
D) 1