1) Based on animal studies, the most radiosensitive gestational age in terms of embryonic mortality is approximately:
A. 0-1 weeks
B. 1-4 weeks
C. 4-8 weeks
D. 8-15 weeks
E. 15-40 weeks
2) Which of the following pairs of gestational stage and linked radiation-induced developmental defect is CORRECT?
A. preimplantation – congenital malformations
B. organogenesis – prenatal death
C. early fetal period – mental retardation
D. late fetal period – neonatal death
E. entire gestation period – malformations of the kidney
3) Which of the following statements is FALSE concerning ionizing radiation’s effects on the developing embryo or fetus?
A. Irradiation in utero produces stochastic effects, examples of which are prenatal death and congenital malformations.
B. Congenital malformations can be a consequence of irradiation during the organogenesis period.
C. The data obtained for people who were irradiated in utero during the atomic bombings of Hiroshima and Nagasaki support the hypothesis that irradiation during fetal development may cause growth and mental retardation.
D. The dose, dose rate and stage of gestation are important determinants of the type and severity of developmental injury.
E. Ionizing radiation exposure causes a spectrum of developmental defects.
4) Which of the following gestational ages in humans is thought to be the most sensitive time for radiation-induced neonatal death?
A. 0-2 weeks
B. 2-6 weeks
C. 6-15 weeks
D. 15-25 weeks
E. 25-40 weeks
5) A woman begins working at a nuclear power plant on her 18th birthday. According to NCRP guidelines, when she reaches her 20th birthday, she would have been permitted a total work-related lifetime effective dose equivalent of:
A. 5 mSv
B. 50 mSv
C. 100 mSv
D. 200 mSv
E. 300 mSv
6) Suppose that on her 21st birthday, the same radiation worker as described in the previous question declared that she was 3 months pregnant. What additional dose limit to the fetus has the NCRP recommended for the duration of her pregnancy?
A. She would not be allowed any additional radiation exposure once the pregnancy was declared
B. 1 mSv
C. 10 mSv
D. 50 mSv, assuming that she had no measurable exposure yet that year
E. 0.5 mSv per month
7) What are the NCRP maximum permissible annual dose limits for the eye and to localized skin areas for radiation workers?
A. 50 mSv to the eye and skin
B. 150 mSv to the eye and skin
C. 150 mSv to the eye and 50 mSv to the skin
D. 150 mSv to the eye and 500 mSv to the skin
E. 500 mSv to the eye and150 mSv to the skin
8) In the United States, the average annual effective dose equivalent from all sources of radiation is closest to:
A. 0.2 mSv
B. 1 mSv
C. 5 mSv
D. 15 mSv
E. 50 mSv
9) Which of the following pairs of person’s occupation or status and maximum annual effective dose equivalent permitted is CORRECT? (These values exclude doses from exposure to background radiation, both natural and man-made)
A. radiation oncologist – 200 mSv per year
B. member of the general public – 1 mSv per year
C. sixteen-year old high school student who works part time in a laboratory – 0 mSv
D. nuclear power plant worker – 10 mSv
E. relative who transports a radiotherapy patient to and from treatment – 20 mSv
10) The Maximum Permissible Dose (MPD) recommended annually for radiation workers:
A. is the dose workers would receive if the workplace adhered strictly to the principles of ALARA
B. is 100 times higher than that for members of the general public
C. is greater under NCRP guidelines than ICRP guidelines for young workers, but is greater under ICRP guidelines for older workers
D. includes dose contributions from natural background radiation only
E. includes dose contributions from man-made sources only
11) In estimating the doses to individuals and their critical organs, and in assessing potential risks to both individuals and populations, various correction factors are required. Which one of the following statements regarding these terms is INCORRECT?
A. For a particular tissue or organ, the proportion of the risk for stochastic effects resulting from uniform, whole-body irradiation is called the “tissue weighting factor.”
B. The dose equivalent to the most sensitive tissue or organ following uniform, whole-body irradiation is called the “committed dose equivalent.”
C. The sum of the individual dose equivalents received over a defined time period by an irradiated population is called the “collective dose.”
D. The average absorbed dose in a particular tissue or organ that is weighted for the radiation quality, is called the “equivalent dose.”
E. The sum of weighted equivalent doses for all tissues and organs of the body is called the “effective dose.”
12) Radiation-induced deterministic effects can be produced as a consequence of either therapeutic or accidental radiation exposures. Which of the following statements concerning deterministic effects is FALSE?
A. The severity of a deterministic effect varies with dose and there is a threshold dose below which the effect does not occur.
B. One example of a deterministic effect is a radiation-induced cataract.
C. Examples of deterministic effects are the increased incidence of heart disease observed in Hodgkin’s disease survivors who received mediastinal irradiation and in breast cancer patients who were treated with radiotherapy.
D. A deterministic effect is one that is random in nature and for which the probability of the effect occurring is a function of radiation dose.
E. Deterministic effects include radiation-induced normal tissue complications that can remain latent for extended periods, but then are exacerbated by the addition of chemotherapy agents such as adriamycin.
13) siRNAs and miRNAs:
A. bind to and inhibit the replication of specific genes
B. stimulate RNA synthesis
C. are typically 1 kb in size
D. stimulate protein synthesis
E. bind to and inhibit the transcription of specific genes
14) A cDNA library is:
A. composed of the intronic regions of genes
B. a population of bacteriophage containing DNA fragments that together comprise the entire genome of an organism
C. “back-engineered” using cytoplasmic proteins
D. “back-engineered” using cytoplasmic mRNAs
E. generated for human cells using 100 or fewer bacteriophage
15) Which of the following statements concerning gel electrophoresis is TRUE?
A. DNA molecules are negatively charged so will migrate toward the positive electrode of the electrophoresis apparatus.
B. SDS is a detergent used for the separation of DNA molecules of different size.
C. The higher the concentration of agarose in a gel, the faster DNA molecules will migrate.
D. Polyacrylamide gels are used to separate large DNA molecules whereas agarose gels are used for smaller-sized DNAs.
E. The higher the molecular weight of the molecule, the faster it will migrate through a gel.
16) Which of the following statements is CORRECT concerning techniques to clone genes?
A. Bacteriophage λ is often used as a vector in cloning experiments because it contains genes that encode for antibiotic resistance
B. When information is available concerning the amino acid sequence of a particular protein, a unique oligonucleotide probe can be synthesized for cloning that gene.
C. Functional complementation requires the use of the Southern hybridization technique.
D. An antibody probe is used to screen a cDNA library.
E. When some or all of the genetic code of a particular gene is available, a complementary DNA probe can be constructed and used to screen the genomic library.
17) Which of the following statements is TRUE concerning the use of PET imaging?
A. 18F-2-deoxy-2-fluoro-D-glucose (18F-FDG) has a radioactive half-life of approximately 10 days.
B. A PET imaging camera detects positrons generated from the decay of radiopharmaceuticals.
C. The uptake of 18F-FDG is typically lower in areas of inflammation.
D. An important advantage to using 18F-FDG-PET/CT fusion images for radiotherapy treatment planning is that they provide both functional and anatomical information.
E. Tumors tend to show a reduced uptake of 18F-FDG.
18) Which of the following assays would best determine whether a particular radiation sensitivity syndrome is characterized by defective repair of DNA double-strand breaks?
A. quantitation of γ-H2AX foci
B. western blot
C. alkaline comet assay
D. southern hybridization
E. northern hybridization
19) Pulsed-field gel electrophoresis can be used to:
A. determine a cell’s karyotype.
B. detect DNA interstrand crosslinks.
C. separate protein molecules on the basis of both molecular weight and charge.
D. monitor the repair/rejoining of large pieces of DNA after the production of double-strand breaks.
E. determine the rate of base versus nucleotide excision repair.
20) Which one of the following is NOT a method for studying gene expression at the protein level?
A. immunohistochemistry
B. ELISA
C. northern blots
D. western blots
E. two-hybrid screening
