Deck 32: Cellular Radiobiology

Question 1

The DO represents the ______________ dose for human cells.

A) mean survival
B) mean lethal
C) 50% survival
D) 50% lethal

Answer 1

mean lethal

Question 2

The mean lethal dose for high-LET radiation is _______ than after low-LET radiation.

A) higher
B) lower
C) the same
D) unknown

Answer 2

lower

Question 3

According to target theory, the target molecule of a cell is _____________________.

A) any molecule in the cell
B) the DNA in the nucleus
C) a water molecule
D) a protein macromolecule

Answer 3

the DNA in the nucleus

Question 4

If oxygen is present during high-LET radiation the effect of radiation is __________.

A) reduced
B) minimal
C) maximal
D) the same

Question 5

The DQ is the ____________ dose for irradiation of human cells.

A) single-target
B) multi-hit
C) lethal
D) threshold

Question 6

A target molecule that is __________________ will always cause cell death.

A) inactivated
B) damaged
C) hit
D) ionized

Question 7

A hit to a cell target can occur from a(n) _________________ effect.

A) indirect
B) direct
C) oxygen
D) Both A and B

Question 8

The _______-target, ______-hit model of radiation-induced cell death applies to simple cells only.

A) single, single
B) multiple, multiple
C) multiple, single
D) single, multiple

Question 9

The probability of a hit is increased with ______ oxygen and ______ LET radiation.

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

Question 10

Which of the following types of radioactive particle has the highest LET?

A) Alpha particle
B) X-ray
C) Gamma-ray
D) Proton

Question 11

Irradiation hits occur through ___________________.

A) indirect effects
B) direct effects
C) excitation events
D) Both A and B

Question 12

Human cells are most radiosensitive during the _________ phase of the cell cycle.

A) gap2
B) gap1
C) mitosis
D) synthesis

Question 13

If oxygen is present during low-LET radiation the effect of radiation is __________.

A) reduced
B) minimal
C) maximal
D) the same

Question 14

The x-intercept of a low LET cell-survival curve is _______ than a similar high LET cell-survival curve.

A) the same
B) larger
C) smaller
D) None of the above

Question 15

The lethal effects of cell irradiation are measured by cell _______________.

A) death
B) survival
C) damage
D) mutation