Final LRA 215 Questions and Answers Already Graded A

Final LRA 215 Questions and Answers Already Graded A As LET _____, the RBE _____. increases, increases Tissue is_____ radiosensitive under high oxygen conditions and ____ radiosensitive under hypoxic conditions more, less Tissues that are _____ with a _____ metabolic rate are more radiosensitive. immature, high If a response to radiation is expected, no matter how small the dose, then that dose-response is _____. nonthreshold The human application of radioprotective agents would be fatally toxic The possible beneficial effect of a small amount of radiation is called _______ hormesis A_____response to radiation is directly proportional to the dose received linear Radiation induced genetic damage follows a____ dose-response relationship linear-nonthreshold The RBE of diagnostic x-rays is equal to __ 1 Human cells cannot recover from radiation damage after there is___ interphase death Studies of the effects of radiation show that low doses may____ Stimulate the immune system Extend lifespan Stimulate hormonal responses A dose of 10Gy given to a patient in 5 doses of 2Gy per day is a ____dose fractionated dose The LET of diagnostic x-ray is____keV/um. 3.0 _____is a measure of the rate that energy is transferred from ionizing radiation to soft tissue LET Which dose response relationship can follow a sigmoid curve? Nonlinear-threshold Fractionation and protraction are used for radiation therapy because they allow the patient to____ Recover between doses Have higher total doses Repair damaged tissues The human dose-response relationship at low ranges of radiation is calculated using____ Extrapolation form high ranges A protracted dose of radiation is given______ over a long period of time The law of_____states that the radiosensitivity of living tissue is a function of the metabolism and maturation of that tissue Bergonie and Tribondue Humans are the most radiosensitive during_____ Fetal stages ____are among the most radioresistive species Cockroaches There are usually a_____before the symptoms of acute radiation syndromes appear latent period About half of the population will experience skin erythema following a localized dose of ____Gy 5 The central nervous system syndrome occurs following a whole body dose of ____Gy 50 A single chromosome aberration represents_____to the DNA within the chromosome severe damage Some radiation victims of_____syndrome(s) may recover completely hematologic Death from acute radiation exposure follows a____dose-response relationship nonlinear,threshold A dose of___Gy or more to a small area of the body can cause skin erythema 2 What would be the most likely immediate response to a whole body dose of 2Gy? Diarrhea, nausea, and vomiting The minimum dose lethal to humans is____ Gy to the whole body 2 During the latent period, the radiation victim experiences well-being Localized dose of 7Gy to the skin can cause permanent hair loss The LD 50/60 for humans is approximately _____Gy 3.5 High doses of radiation to a localized area can be lead to___ of tissues and organs in that area Reduction in size Shrinkage Total loss of function The destruction of___cells in the intestinal lining causes death from GI syndrome Stem cells The LD50/60 is the dose of radaition to the whole body that will result in death within____to____% of the irradiated population 60 days, 50% Gonadal responses to radiation have been observed doses as low as ___Gy 0.1 The stem cells of the ovaries multiply during____ fetal growth Skin effects from localized doses of radiation follow a____dose-response relationship nonlinear-threshold A local dose of___rad(s) or more can cause gonadal dysfunction 10 Immediately following a whole body dose of 10 Gy the victim would experience (a)______ Prodromal symptoms The most radiosensitive cells in the hematopoietic system of the human body are the___ lymphocytes Ovaries are most radiosensitive during_____ Fetal growth Early childhood A person subjected to 50 Gy to the whole body may survive for___ before death occurs 3 days A subject would not experience____following a dose high enough to cause CNS syndrome hematologic syndrome Studies of A-bomb survivors indicate that leukemia has a___dose-response relationship to radiation linear-nonthreshold Our information on the genetic effects of radiation has come from studies of___ Mice Fruit Flies A___effect increases in incidence but not severity as the dose increases stochastic The most radiosensitive period during pregnancy for radiation induced congenital abnormalities id during first trimester Chronic low doses of radiation have _____ effect on fertility. NO Radiation induced skin cancer in radiotherapy patients has occured with____ A threshold dose-response The theory of radiation hormesis suggests that radiation doses below 0.1 mGy are beneficial Relative risk is___ observed cases/expected cases Low doses of radiation have been shown to cause _____. chromosome damage Data showing radiation-induced human genetic abnormalities _____. does not exist People who had radiation treatments to their thymus gland as children later showed excess risk for _____. thyroid cancer A study of an irradiated population which showed a relative risk factor below 1.0 would indicate that the population had a _____ risk. reduced Ankylosing spondylitis patients treated with radiation showed an increased incidence of___ leukemia Radiation protection guidelines are based on _____. stochastic effects of radiation ____is a stochastic effect of radiation exposure Cancer People who were employed painting radium watch dials later showed excess risk for _____ cancer. Bone Cancer Radiation induced leukemia has a latent period of ____years 4-7 An epidemiological study of the stochastic effects of very low doses of radiation requires a population of _____ of people. millions The threshold dose for cataract formation is known to be____mSv of acute exposure of the eyes 2 It is difficult to link cancer to radiation exposure because it occurs____in the population in high proportion The human application of radioprotective agents would Be fatally toxic The stem cells of the ovaries multiply during Fetal Growth Gonadal responses to radiation have been observed at doses as low as .01 Gy