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Rad Bio Chapter 9

Terms in this set (60)

most radiation-induced genetic mutations are:
recessive mutations
spontaneous mutations in human genetic material cause a wide variety of diseases including:
1. down syndrome
2.hemophilia
3. sickle cell anemia
1, 2, and 3
epidemiologic studies are of significant value to scientists who use the information from these studies to formulate dose-response estimates to predict the risk of:
cancer in human populations exposed to low doses of ionizing radiation
which of the following measures the effectiveness of ionizing radiation causing mutations?
doubling dose
recent studies of atomic bomb survivors tend to support the _____ risk model over the ____ risk model
relative, absolute
the linear dose-response model is used to establish radiation protection standards because it accurately reflects the effects of:
high LET radiation at higher doses
the number of excess cancers, or cancers that would not have occurred in a given population in question without pre-exposure to ionizing radiation may be predicted by which of the following:
1 and 3 only (absolute and relative)
after the radiation accident at the Chernobyl nuclear power plant in 1986, many children in Poland and some other countries were given potassium iodide in attempted to prevent:
thyroid cancer
When exposure to ionizing radiation causes proliferation of the white blood cells, the radiation-induced disease that occurs is
leukemia
radiation can induce genetic damage by which of the following means?
altering the essential base coding sequence of DNA
cataracts, leukemia, and genetic mutations are examples of:
measurable radiation-induced biologic damage
for a recessive mutation to appear in an offspring:
both parents must have the same genetic defect
using the doubling dose concept to measure the effectiveness of ionizing radiation causing mutations, 9% of the offspring in each generation are born with mutations in the absence of radiation other than background levels, administration of the doubling dose to all members of the population eventually would increase the number of mutations to:
18%
which of the following groups of individuals received radiation treatment that indicated radiation can cause breast cancer when healthy breast tissue was exposed to radiation?
patients treated for benign postpartum mastitis
during the embryonic stage of development:
all life forms seem to be most vulnerable to radiation exposure
which of the following are examples of stochastic effects?
cancer and genetic defects
based on the revised atomic bomb data from Hiroshima and Nagasaki, radiation-induced leukemias and solid tumors in the survivors may be attributed predominately to:
gamma radiation exposure
radium decays with a half-life of 1622 years to the radioactive element:
radon
after the 1986 Chernobyl nuclear power plant accident, approximately how many people worldwide receive some exposure to fallout?
400,000
young women who painted watch dials with radium in some factories in New Jersey in the 1920s and 1930s eventually developed which of the following conditions as a consequence of their exposure to radiation:
1. osteoporosis
2. osteogenic sarcoma
3. Carcinomas of the epithelial lining of the nasopharynx and paranasal sinuses
1, 2, and 3
the only concrete evidence that ionizing radiation causes genetic effects comes from:
extensive experiments with fruit flies and mice at high radiation
which of the following led to the development of the doubling dose concept?
animal studies of radiation-induced genetic effects
members of which of the following groups of radiologic technologists have demonstrated the greatest risk of dying of breast cancer as a consequence of their occupation?
technologists who began working before 1940
which of the following are mutagens?
1. elevated temperatures
2. ionizing radiation
3. viruses
1, 2, and 3
mutant genes cannot properly govern the cell's normal chemical reactions or properly control the sequence of ______ in the formation of specific proteins
amino acids
cataracts, leukemia, and genetic mutations are examples of measurable radiation induced biologic damage
true
if a threshold relationship exists between a radiation dose and a biologic response, even the smallest dose of ionizing radiation will have some biologic effect on a living organism
false, nonthreshold relationships even the smallest dose will have an effect
the biological effects on ionizing radiation (BEIR) committee believes that the linear quadratic threshold curve of radiation dose response is a more accurate reflection of stochastic and genetic effects at low dose levels from low LET radiation
false, non-threshold radiation dose response curve
late responses in the body to radiation exposure that do not have threshold, occur in an arbitrary or probabilistic manner, and have a severity that does not depend on dose, are classified as late stochastic effects
true
low level doses are consideration for patients and personnel exposed to ionizing radiation as a result of diagnostic imaging procedures
true
distinguishing radiation induced cancer by its physical appearance is relatively easy because it looks very different from cancers caused by other agents
false, it's difficult to distinguish
any non lethal radiation dose received by the germ cells can cause chromosome mutations that may be transmitted to successive generations
true
a genetic disorder is present in approximately 50% of all living births in the US
false, 10% of all living births
the impact of the atomic bomb dosimetry revision is a significant increase in cancer risk estimates
true
many cases of radiation induced skin cancer among radiation workers have been documented in recent years
false, have been documented in the early 1900s
radium watch dial painters of the 1920s and 1930s provide proof of radiation cataractogenesis
false, provide proof of radiation carcinogensis
conclusive proof exists that low-level ionizing radiation doses (those below 0.1 Sv) cause a significant increase in the risk of malignancy
false, there is no proof
technologists who entered the medical radiation industry in 1950 or later have demonstrated a somewhat higher risk of dying from leukemia compared with individuals who entered the workforce before 1950
false, workers BEFORE 1950s had more of a risk
the term linear quadratic means that the equation that best fits the data has terms that depend on dose (linear) and also dose squared (quadratic)
true
currently, evidence of radiation induced hereditary effects has not been observed in persons employed in diagnostic imaging or in patients undergoing radiologic examinations
true
irradiation of the embryo fetus during the first 12 weeks of development doses in excess of 200 mSv frequently results in death or severe congenital abnormalities
true
the effect of low-level ionizing radiation on the embryo fetus can only be estimated
true
follow up studies of the Japanese atomic bomb survivors of Hiroshima and Nagasaki who did not die of ARS have not demonstrated late deterministic and stochastic effects of ionizing radiation
false, they have demonstrated late effects
for humans the doubling dose is estimated to have a mean value of 1.56 Sv
true
genetic (hereditary) effects occur as a result of radiation induced damage to the DNA molecule in the sperm or ova of an adult
true
information obtained from radiation dose response curve can be used to predict the risk of malignancy in the human population exposed to low levels of ionizing radiation
true
the lens of the eye contain opaque fibers that transmit light
false, lens of the eye contain transparent fibers
organ atrophy is the most important late stochastic somatic effect caused by exposure to ionizing radiation
false, cancer is the most important late effect
the 1989 BIER V Report supported use of linear-quadratic model of radiation dose-response for leukemia only
true
during the 1940s and early 1950s, to reduce an enlarged thymus glad in infants with respiratory disorders, physicians treated the babies with therapeutic doses of x-radiation (1.2 to 60 Gyt) resulting in an substantial dose to the nearby thyroid gland; this caused thyroid nodules and carcinomas some 20 years later
true
cancer and genetic defects are examples of _______ effects
stochastic
some examples of measurable late biologic damage are:
1. cataracts
2. leukemia
3. nausea and vomiting
4. genetic mutations
1, 2, and 4 only
which of the following provided the foundation for the sigmoid or S shaped (non-linear) threshold curve of radiation dose response?
data from a human populations observed after acute high doses of radiation
the linear nonthreshold curve implies that biologic response is:
directly proportional to the dose
reevaluation of the quantity and type of radiation that was released in the atomic bombing of the cities of Hiroshima and Nagasaki has led to revised atomic bomb data in which radiation-induced leukemia and solid tumors may now be attributed predominately to:
gamma radiation exposure
the radiation dose-response relationship is demonstrated graphically through the use of a curve that maps the observed effects of radiation exposure in relation to the dose of radiation received. Which of the following curves expresses a linear quadratic nonthreshold dose response?
C. I/)
during the 10 years immediately after the 1986 Chernobyl nuclear power station accident, which of the following was the most pronounced health effect observed?
dramatic increase in thyroid cancer in children living in the regions where the heaviest radioactive contamination occurred
the early demise of the experimental animals exposed to non-lethal doses of ionizing radiation actually resulted from:
induction of cancer
according to the data from studies performed on US radiologic technologists, individuals who began working before 1950 had a somewhat higher risk of dying of ______ when compared with technologist who started working in 1950 and later.
leukemia
most diagnostic procedures result in equivalent doses:
less than 0.01 Sv
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