Deck 3: Cellular Effects of Radiation

Question 1

_____ is a measure of the capacity of a specific ionizing radiation to produce a specific biological effect, expressed relative to a reference radiation, such as radium gamma rays or 200-volt x-rays.

A) Linear energy transfer (LET)
B) Relative biologic effectiveness (RBE)
C) Oxygen enhancement ratio (OER)
D) Radiolysis of water

Answer 1

B

Question 2

Which of the following affect cell response to radiation?
1. linear energy transfer (LET)
2. relative biologic effectiveness (RBE)
3. oxygen enhancement ratio (OER)

A) 1 only
B) 1 and 2 only
C) 3 only
D) 1, 2 and 3

Answer 2

D

Question 3

Cells which are considered highly radiosensitive include

A) lymphocytes, spermatagonia, erythroblasts, and intestinal crypt cells
B) endothelial cells, osteoblasts, spermatids, and fibroblasts
C) muscle cells, nerve cells, and chondrocytes
D) all cell types have the same radiosensitivity

Answer 3

A

Question 4

_____ is a measure of the energy transferred to material as an ionizing particle travels through it. This measure is used to quantify the effects of ionizing radiation on biological specimens.

A) Linear energy transfer (LET)
B) Relative biologic effectiveness (RBE)
C) Oxygen enhancement ratio (OER)
D) Radiolysis of water

Question 5

_____ creates a stickiness on a macromolecule, causing it to connect to another macromolecule, or to another section of the same molecule.

A) Main-chain scission
B) Cross-linking
C) Point lesion
D) Radiolysis

Question 6

At the doses received in diagnostic radiology, only _____ types of chromosomal aberrations are seen.

A) single-hit
B) multi-hit
C) reciprocal translocation
D) division delay

Question 7

Which of the following are considered to be the most radiosensitive phases of the cell cycle?

A) mid- to late S-phase
B) G1 and late S-phase
C) G1 into early S-phase
D) all stages of the cell cycle have the same radiosensitivity

Question 8

Which of the following is considered to be the most radiosensitive part of a cell?

A) mitochondria
B) centrioles
C) lysosomes
D) nucleus

Question 9

The breakdown of water using radiation is termed

A) oxygen effect
B) mutation
C) translocation
D) radiolysis

Question 10

_____ is said to occur when an original ionizing event occurs directly on that macromolecule, e.g., DNA.

A) Direct interaction
B) Indirect interaction
C) Radiolysis
D) Interphase death

Question 11

_____ occurs when the thread or backbone of a long-chain molecule is broken, resulting in numerous smaller molecules.

A) Main-chain scission
B) Cross-linking
C) Point lesion
D) Radiolysis

Question 12

At low radiation doses, most cellular radiation damage is the result of

A) main-chain scission
B) cross-linking
C) point lesions
D) maturation depletion

Question 13

The primary effect of irradiating macromolecules in vitro include:
1. main-chain scission
2. cross-linking
3. point lesions

A) 1 and 2 only
B) 2 and 3 only
C) 3 only
D) 1, 2 and 3

Question 14

Irradiation of macromolecules may result in disturbance of single chemical bonds, which create molecular lesions, also known as

A) point lesions
B) interphase death
C) maturation depletion
D) cell death

Question 15

An uncharged molecule that contains a single unpaired electron in its outermost shell, which makes it chemically unstable and highly reactive, is termed a

A) free radical
B) HeLa
C) dicentric
D) translocation

Question 16

Which of the following are considered to be the most radioresistant phases of the cell cycle?

A) mid- to late S-phase
B) G1 into early S-phase
C) G1 and late S-phase
D) all stages of the cell cycle have the same radioresistance

Question 17

Chromosome produced radiation damage can be analyzed during which portion of the cell cycle?

A) prophase
B) metaphase
C) anaphase
D) telophase

Question 18

Cell death which occurs before mitosis is termed

A) RNA death
B) DNA death
C) interphase death
D) prophase death

Question 19

Undifferentiated, precursor, or stem cells are other names for

A) mature cells
B) immature cells
C) polymers
D) proteins

Question 20

_____ refers to the enhancement of therapeutic or detrimental effect of ionizing radiation due to the presence of oxygen.

A) Linear energy transfer (LET)
B) Relative biologic effectiveness (RBE)
C) Oxygen enhancement ratio (OER)
D) Radiolysis of water

Question 21

_____ occurs if the initial ionizing incident takes place on a distant noncritical molecule, which then transfers the ionization of energy to another molecule.

A) Direct interaction
B) Indirect interaction
C) Interphase death
D) Reduction division

Question 22

Which of the following is a graphical representation of the relationship between radiation dose and observed response, in which any dose may have a potential effect, and there is a direct relationship between dose and effect?

A) nonlinear dose-response curve
B) linear dose-response curve
C) linear quadratic dose-response curve
D) threshold dose-response curve

Question 23

Which of the following is used to describe cell damage from radiation that is not sufficient to kill the cell?

A) sublethal damage
B) duplication effect
C) cell division
D) replication

Question 24

Of the stages of mitosis, which is the most radiosensitive?

A) prophase
B) anaphase
C) metaphase
D) telophase

Question 25

Which of the following is most commonly acted upon directly by ionizing radiation to produce indirect effects?

A) lipids
B) proteins
C) carbohydrates
D) water

Question 26

Why is free radical formation considered such a threat to humans?

A) free radicals produce scatter radiation
B) free radicals can penetrate any type of radiation shielding
C) free radicals have been proven to lengthen our lifespan
D) free radicals have been observed to produce toxic effects

Question 27

A graphical representation of observed effects compared with radiation dose is termed a

A) dose-response relationship (curve)
B) pie-graph
C) bar graph
D) line graph

Question 28

The term _____ is used to describe the effects of radiation on cells that are adjacent to those directly affected by radiation.

A) chromosomal aberration
B) translocation
C) nonthreshold
D) bystander effects

Question 29

How does oxygen retention affect cell radiosensitivity?

A) increases radiosensitivity
B) decreases radiosensitivity
C) eliminates radiosensitivity
D) has no effect on radiosensitivity

Question 30

On a dose-response curve, the point where radiation begins to produce an effect is known as the

A) shoulder
B) quadratic point
C) threshold
D) toe

Question 31

As linear energy transfer (LET) increases, how is relative biologic effectiveness (RBE) affected?

A) with an increases in LET, RBE also increases
B) with an increase in LET, RBE decreases
C) with an increase in LET, RBE is neutralized
D) RBE is not affected by LET

Question 32

According to the target theory, which of the following is considered to be the critical target in the cell?

A) RNA
B) centrioles
C) lysosomes
D) DNA

Question 33

The type of irradiation damage most likely to cause abnormalities in base sequences, and thus cell mutation, would be

A) single-strand breaks
B) double-strand breaks
C) cross-linking
D) base damage

Question 34

Which portion of the cell survival curve proves that some damage must accumulate before cell death can occur?

A) shoulder
B) straight-line
C) toe
D) quadratic

Question 35

Nonthreshold

A) means that an observed response is directly proportional to the dose
B) means that an observed response is not directly proportional to the dose
C) assumes that there is a radiation level reached under which there would be no effects observed
D) assumes that any radiation dose produces an effect

Question 36

Which of the following is considered to be most radiosensitive?

A) fetus
B) pediatric patient
C) teenage patient
D) adult patient