Chapter 24 - Radiation Toxicology

Question 1

The most frequent type of DNA damage in mammalian cells produced by low LET radiation exposure is…

A. Double-strand breaks

B. Single-strand breaks

C. DNA-protein crosslinks

D. DNA dimers

Answer 1

B. Single-strand breaks

Question 2

An example of a pure gamma ray emitter is..

A. Technetium 99m

B. Carbon 14

C. Sodium 22

D. Oxygen 16

Answer 2

A. Technetium 99m

Question 3

Photons interact with matter in all of the following ways except…

A. Pair production

B. Dark energy production

C. Photoelectric effect

D. Compton effect

Answer 3

B. Dark energy production

Question 4

Internal conversion produces…

A. An atom without an orbital electron

B. An atom of higher atomic number

C. An atom of lower atomic number

D. An electron from a gamma ray

Answer 4

A. An atom without an orbital electron

Question 5

If a photon possesses energy of the order 1.02 MeV, it is capable of…

A. Splitting He atoms

B. Producing a positron and an electron

C. Converting a neutron into a proton and electron

D. Creating an alpha particle

Answer 5

B. Producing a positron and an electron

Question 6

Which of the following has the least ability to penetrate the skin?

A. Beta particle

B. Neutron

C. X-ray

D. Gamma rays

Answer 6

A. Beta particle

Question 7

Alpha particles are most dangerous when they…

A. Do not have relativistic velocities

B. Are produced from He

C. Are inhaled

D. Are in contact with the skin

Answer 7

C. Are inhaled

Question 8

The biological effects of radiation are due to all of the following except…

A. Breaking hydrogen bonds

B. Free radical generation

C. Breaking covalent bonds

D. Forming coordination complexes with biological metals

Answer 8

D. Forming coordination complexes with biological metals

Question 9

Combination of an inner-shell electron with a nuclear proton is called…

A. Electron capture

B. Positron emission

C. Beta-decay

D. None of the above

Answer 9

A. Electron capture

Question 10

The occupational limits for radiation developed in a 1990 document by the Internal Commission on Radiation Protection are…

A. 100mSv in 5 yrs

B. 250mSv in 5 yrs

C. 500mSv in 5 yrs

D. 1 Sv in 5 yrs

Answer 10

A. 100mSv in 5 yrs

Question 11

Much of the DNA damage from high LET (linear energy transfer) radiation…

A. Is readily repairable

B. Results from localized clusters of ionization

C. Occurs in many cells along a tract receiving a small dose

D. All of the above

Answer 11

B. Results from localized clusters of ionization

Question 12

The late health effect of radium ingestion in radium dial painters was…

A. Acute myelogenous leukemia

B. Alpastic anemia

C. Osteogenic sarcoma

D. Multiple myeloma

Answer 12

C. Osteogenic sarcoma

Question 13

Children under 18 at the time of the Chernobyl nuclear accident developed the greatest increase in the incidence of…

A. Lung cancer

B. Liver cancer

C. Thyroid cancer

D. Colon cancer

Answer 13

C. Thyroid cancer

Question 14

The lung cancer risk in uranium miners is due to…

A. Uranium 234

B. Lead 214

C. Radon 226 and its decay products

D. Thorium 234

Answer 14

C. Radon 226 and its decay products

Question 15

All of the following are true of indoor radon exposure except…

A. Open flames in a house produce a higher exposure

B. Urban areas have the same radon levels as rural areas

C. Smokers have a higher risk per unit of exposure

D. Particle size can change the dose delivered to the lungs

Answer 15

B. Urban areas have the same radon levels as rural areas

Question 16

The largest percentage of natural background radiation that the human body receives is from…

A. Short-lived daughter isotopes of radon

B. Cosmic rays

C. Medical X-rays

D. Dietary intake of potassium 40

Answer 16

A. Short-lived daughter isotopes of radon

Question 17

The largest amount of terrestrial background radiation comes from…

A. Nitrogen, oxygen and silicon

B. plutonium, thallium and technetium

C. Sodium, potassium and cesium

D. Uranium, thorium and potassium

Answer 17

D. Uranium, thorium and potassium

Question 18

A process that creates the same product nuclei as position emission is…

A. Alpha decay

B. Gamma ray production

C. Electron capture

D. Beta decay

Answer 18

C. Electron capture

Question 19

The characteristic of alpha particles which causes a high energy loss per path length and a high ionization density along the track length is called…

A. High Compton effect

B. High linear energy transfer

C. High photoelectric effect

D. High energy pair production

Answer 19

B. High linear energy transfer

Question 20

Beta particles moving near the speed of light…

A. Have a wavelength in the visible range

B. Rarely interact with matter

C. Must have relativistic effects applied to them

D. Frequently decompose into gamma rays and neutrinos

Answer 20

C. Must have relativistic effects applied to them

Question 21

The unit of absorbed dose for ionizing radiation is…

A. Rem

B. sievert

C. Rotegen

D. Gray

Answer 21

D. Gray

Question 22

The unit of equivalent dose for ionizing radiation is…

A. Rem

B. Sievert

C. Rotegen

D. Gray

Answer 22

B. Sievert

Question 23

The term-effective dose of ionizing radiation…

A. Is a dose that causes necrosis of particular cell types

B. Is the equivalent dose divided by the weight of body tissue

C. Allows for a direct comparison of the cancer risk from different partial or whole-body doses

D. Is a dose that kills greater than 99% of malignant cells in a particulat tissue

Answer 23

C. Allows for a direct comparison of the cancer risk from different partial or whole-body doses

Question 24

Beta particles are emitted with a continuous energy spectrum because of the simultaneous emission of a/an…

A. Protein

B. Gamma ray

C. X-ray

D. Antineutrino

Answer 24

D. Antineutrino