Science & Education
1. Which of the following statements correctly describes
chromosomal aberrations in stimulated peripheral lymphocytes?
A. They can be used to assess whole-body radiation exposures.
B. They can be used to detect a dose of 1 cGy.
C. They can be used to measure a total body dose of 10 Gy 3 weeks after
D. The number of interchange aberrations is a linear function of dose for x–rays.
2. Which of the following portions of the gastrointestinal
tract is most radiosensitive to cell killing?
C. Small intestine
D. Large intestine
3. Which of the following syndromes is associated with the greatest sensitivity
A. Bloom syndrome
B. Ataxia telangiectasia
C. Fanconi anemia
D. Xeroderma pigmentosum
4. Which of the following represents the minimum dose range
that results in an expected 5%–30% prevalence of nausea following acute
A. 0.01–0.1 Gy
B. 0.1–0.25 Gy
C. 0.75–1.25 Gy
D. More than 10 Gy
5. Which of the following represents the most likely
consequence of an acute total body exposure to 1 Gy of x–rays?
B. Decrease in lymphocyte count
D. Sterility in a female
6. For each of the
following items (1–4), with match its dose (A–D) at single acute x-ray exposures.
1. Dose producing the cerebrovascular syndrome
2. Estimated dose to double the natural mutation rate
3. Typical LD 50/5 (ie, gastrointestinal death)
4. Typical LD 50/60 in humans
D. 100 Gy
C. 10 Gy
B. 4 Gy
A. 1 Gy
7. Which of the following effects would be seen as a
consequence of a total body exposure to 1.5 Gy of x-rays?
A. Vision-impairing cataracts of the ocular lens
B. Dicentric chromosomes in peripheral lymphocytes
C. Skin erythema
E. Increased carcinogenesis from 25 % to 50%
8. An acute whole-body exposure of 1 Gy of low-LET radiation
will cause which of the following effects? (Select all that apply.)
A. Vomiting in 95% of those exposed
B. Diarrhea in 95% of those exposed
C. Temporary sterility in males
D. Permanent sterility in females
E. Decrease in lymphocyte count
9. Which of the following statements best characterizes
total body irradiation of humans after an acute exposure to x-rays?
A. The LD 50/60 is between 3 and 5 Gy.
B. Seizures are likely if the dose exceeds 3 Gy.
C. The nadir in white cell count following a dose of 2 Gy will occur within 6
D. Bone marrow transplants are likely to save persons exposed to more than 15
10. The explosion of a “dirty bomb” made from highly
radioactive material, such as a cobalt-60 teletherapy source, can result in
which of the following? (Select all that apply.)
A. Radiation dose sufficient to cause acute radiation injury
B. Casualties contaminated with radionuclides
C. Psychologic impact on the victims
D. Casualties may present a potential hazard to medical personnel