Multiple Choice Questions

As LET ___, the RBE ___. A. increases, remains the same B. decreases, remains the same C. increases, increases D. increases, decreases

C. increases, increases

Epidemiological studies are of significant value to scientists who use the information from these studies to formulate dose-response estimates to predict the risk of: a) Cancer in human populations exposed to low doses of ionizing radiation b) cataract formation in humans exposed to low doses of ionizing radiation c) radiodermatititis in radiological technologists working in the field between 1970 and 1990 d) radiodermatitis in radiologic technologists working in the field from 1990 to the present time

a) Cancer in human populations exposed to low doses of ionizing radiation

Chromosome aberrations happen when irradiation occurs: a) Early in interphase b) Late in prophase c) At the start of metaphase d) At the end of telophase

a) Early in interphase

________ is the measurement of the rate that energy is transferred from ionizing radiation to soft tissue a) LET b) RBE c) MeV d) OER

a) LET

The random interaction of x-rays with matter produces a variety of structural changes in biologic tissue, including: a) a single-strand break in one chromosome b) more than on break in the same chromosome c) stickiness, or clumping together of chromosomes d) development of square chromosomes

a) a single-strand break in one chromosome b) more than on break in the same chromosome c) stickiness, or clumping together of chromosomes

Which of the following occurs in humans after whole body reception of large doses of ionizing radiation delivered over a short period of time? a) acute radiation syndrome b) hypertension c) multiple sclerosis d) tuberculosis

a) acute radiation syndrome

Epidemiological studies are of significant value to scientists who use the information from these studies to formulate dose-response estimates to predict the risk of: a) cancer in human populations exposed to low doses of ionizing radiation b) cataract formation in humans exposed to low doses of ionizing radiation c) radiodermatitis in radiologic technologists working in the field between 1970 and 1990 d) radiodermatitis in radiologic technologists working in the field from 1990 to the present time

a) cancer in human populations exposed to low doses of ionizing radiation

when biological effects from ionizing radiation demonstrate the existence of a threshold and the severity of that damage increases as a consequence of increased absorbed dose, the events are considered: a) deterministic b) probabilistic c) stochastic d) unimportant

a) deterministic

The term "linear nonthreshold curve" implies that the biologic response to ionizing radiation is _____ the dose. a) directly proportional to b) inversely proportional to c) directly proportional to the square of d) inversely proportional to the square of

a) directly proportional to

When are ovaries most radiosensitive? a) during the fetal stages of life and during early childhood b) after puberty and the onset of menstruation c) from 20 to 30 years of age d) during pregnancy

a) during the fetal stages of life and during early childhood

Chromosome aberrations happen when irradiation occurs: a) late in interphase b) at the start of metaphase c) early in interphase

a) early in interphase

Humans are most radiosensitive during _____. a) fetal stages b) infancy c) adulthood d) old age

a) fetal stages

According to the target theory, if only a few non-DNA cell molecules are destroyed by radiation exposure, the cell probably will: a) not show any evidence of injury after irradiation b) show evidence of injury after irradiation c) show evidence of severe impairment after irradiation d) die

a) not show any evidence of injury after irradiation

A protracted dose of radiation is given _____. a) over a long period of time b) all at one short exposure c) in a series of separate doses d) in two large doses

a) over a long period of time

which of the following describes the ratio of the radiation dose required to cause a particular biological response of the cells or organisms in an oxygen-deprived environment to the radiation dose required to cause an identical response under normal oxygenated conditions? a) oxygen enhancement ratio b) oxygen biologic effectiveness ratio c) oxygen dose-response relationships d) relative biologic effectiveness

a) oxygen enhancement ratio

What constitutes 95% of the single-chromosome breaks: a) restitution b) deletion c) apoptosis

a) restitution

DNA is sometime referred to as? a) the master chemical b) acid c) the big daddy

a) the master chemical

Ionizing events from irradiation are considered to be direct effects if they occur with _____ molecules. a) water b) DNA c) hydrogen ion d) chromosomes

a) water

The extent of energy transfer is dependent upon which of the following? (select all that apply) a) The charge of the radiation b) The energy of the radiation c) The weight of the radiation d) The mass of the radiation

a, b, and c

the most radiosensitive macromolecule is_______ a) protein b) DNA c) mRNA

b) DNA

Which of the following is a hydrogen ion? a) OH* b) H+ c)H*

b) H+

Which of the following measures of lethality may be a more relevant indicator of outcome for humans? a) LD 10/30 b) LD 50/30 c) LD 50/60 d) LD 100/60

b) LD 50/30

When an atom of water is irradiated it first dissociates into _____. a) two water atoms b) an ion pair c) free radicals

b) an ion pair

A type of DNA damage that may not be reversible is a _____. a) cross-linking b) base change or loss c) run breakage

b) base change or loss

Which of the following radiation-induced effects is stochastic? a) cataracts b) breast cancer c) skin erythema d) epilation

b) breast cancer

While passing through a human cell, an x-ray photon interacts with and inactivates the cell's master molecule. What is the consequence for the cell? a) disruption of cell chemistry only b) death c) increased pressure on the cell membrane leading to immediate rupture

b) death

The possible beneficial effect of a small amount of radiation is called _____. a) radiosensitizing b) hormesis c) radioprotection d) protraction

b) hormesis

What do the letters RBE stand for? a) radioactive biological energy b) relative biological effectiveness c) radiation bypass effect d) radiosensitive biological effect

b) relative biological effectiveness

According to target theory, the target molecule of a cell is _____. a) any molecule in the cell b) the DNA in the nucleus c) a water molecule d) a protein macromolecule

b) the DNA in the nucleus

The "direct hit" theory of cell irradiation can be described bu which of the following statements? a) the cell nucleus is struck b) the DNA molecule is struck c) the cell is ionized

b) the DNA molecule is struck

Linear energy transfer is the term used to describe the average energy deposited per_________. a) ionization b) unit length of tract c) gray d) dose

b) unit length of tract

Without medical support, the LD 50/30 for adult humans is estimated to be: a) 1 to 2 gy b) 2 to 3 gy c) 3 to 4 gy d) 4 to 5 gy

c) 3 to 4 gy

As LET increases, the ability of ionizing radiation to cause biologic effects: a) remains constant, not increasing or decreasing b) decreases considerably c) also generally increases until it reaches a maximal value d) decreases slightly

c) also generally increases until it reaches a maximal value

The law of ________states that the radiosensitivity of living tissue is a function of the metabolism and maturation of that tissue? a) Watson and crick b) hurter and drifield c) bergonie and tribondeau

c) bergonie and tribondeau

irradiation hits occur through ______ a) indirect effects b) direct effects c) both indirect and direct effects

c) both indirect and direct effects

Free radicals can be damaging because they are _____. a) unstable b) highly reactive c) both unstable and highly reactive

c) both unstable and highly reactive

Ring chromosomes, dicentric chromosomes, and anaphase bridges are examples of: a) normal chromosomes b) chromosomes about to divide c) distorted chromosomes d) chromosomes that carry appropriate genetic information

c) distorted chromosomes

ARS is actually a collection of symptoms associated with: a) exposure to low level radiation b) exposure to moderate level of radiation c) exposure to high level radiation d) exposure to nonionizing radiation

c) exposure to high level radiation

Two OH* free radicals can join to form _____ molecules. a) organic free radicals b) hydroperoxyl c) hydrogen peroxide d) DNA

c) hydrogen peroxide

Radiation with a high LET: a) carries a low quality factor b) has a low ionization c) is highly ionizing

c) is highly ionizing

Radiation with a high LET: a) carries a low quality factor b) has a low ionization c) is highly ionizing d) equates with a low RBE

c) is highly ionizing

A cytogenetic analysis of chromosomes may be accomplished through the use of a chromosome map. This map is called a: a) chromosomogram b) karyograph c) karyotype d) photocytogenetic plot

c) karyotype

radiation induced genetic damage follows a _______ dose-response relationship. a) nonlinear, nonthreshold b) nonlinear, threshold c) linear, nonthreshold d) linear, threshold

c) linear, nonthreshold

what is the radiation dose response of most radiation induced cancers? a) nonlinear, nonthreshold b) nonlinear, threshold c) linear, nonthreshold d) linear, threshold

c) linear, nonthreshold

A hydroperoxyl radical is formed when a hydrogen free radical combines with: a) a hydrogen ion b) a hydroxl ion c) molecular oxygen d) another hydrogen free radical

c) molecular oxygen

If a response to radiation is expected, no matter how small the dose, then that dose-response is _____. a) linear b) nonlinear c) nonthreshold d) threshold

c) nonthreshold

What is the effect of radiation in a threshold dose-response relationship? a) the severity of radiation damage is limited, regardless of the dose b) a response to radiation will occur with any size dose c) radiation response occurs at a specific dose d) there is no effect

c) radiation response occurs at a specific dose

An indirect effect from ionizing radiation occurs on a _____ molecule. a) target b) DNA c) water d) free radical

c) water

The principal radiation interaction within the human body is with _____. a) DNA b) RNA c) water

c) water

Infection, hemorrhage, and cardiovascular collapse are symptoms that can occur as part of acute radiation syndrome during the: 1. Initial stage 2. Latent period 3. Stage called manifest illness a. 1 only b. 2 only c. 3 only d. 1, 2, and 3

c. 3 only

Which of the following are accessory structures of the skin? 1. hair follicles 2. sebaceous glands 3. sweat glands a) 1 and 2 only b) 1 and 3 only c) 2 and 3 only d) 1, 2 and 3

d) 1, 2 and 3

On which of the following factors does somatic or genetic radiation reduced damage depend? 1. the amount of body area exposed 2. the quantity of ionizing radiation to which the subject is exposed 3. the specific parts of the body exposed a) 1 only b) 2 only c) 3 only d) 1, 2, and 3

d) 1, 2, and 3

which of the following local tissues will experience immediate consequences from high radiation doses? 1. bone marrow 2. male and female reproductive organs 3. skin a) 1 and 2 only b) 1 and 3 only c) 2 and 3 only d) 1, 2, and 3

d) 1, 2, and 3

Each cell's function is determined and defined by the structures of its constituent molecules. If these structures are altered by radiation exposure, the following may result: a) Disturbance of the cell's chemical balance b) Disturbance of cell operation c) Failure of the cell to perform normal tasks d) All of the answers are correct

d) All of the answers are correct

OH*+OH*=________ a) H2O b) HOH+ c) HOH- d) H2O2

d) H2O2

Which of the following is a hydroxyl ion? a) OH- b)H* c) H2O d) OH*

d) OH*

Which of the following are examples of stochastic effects? a) nausea and vomiting b) epilation and fatigue c) diarrhea and leukopenia d) cancer and genetic defects

d) cancer and genetic defects

A graph that describes a response to radiation is referred to as: a) minimum threshold graph b) probability curve c) ALARA curve d) dose response curve

d) dose response curve

What is the radiation dose response relationship of skin erythema? a) nonlinear, nonthreshold b) nonlinear, threshold c) linear, nonthreshold d) linear, threshold

d) linear, threshold

Which dose-response relationship can follow a sigmoid curve? a) linear-nonthreshold b) linear-threshold c) nonlinear-nonthreshold d) nonlinear-threshold

d) nonlinear-threshold

Which of the following types of radioactive particle that will more likely undergo a direct action? a) alpha particle b) x-ray c) gamma ray d) proton

d) proton

Many early radiologists and dentists developed a reddening of the skin caused by exposure to ionizing radiation. This condition is called: a) dermabrerration b) desquamation c) epidermatitis d) radiodermatitis

d) radiodermatitis

Which of the following results of irradiation of cell DNA would have the least potential for lethal consequences? a) double strand break b) covalent cross-link c) mutation d) single-strand break

d) single-strand break

In humans with the gastrointestinal form of ARS, the part of the body most severely affected is the: a) brain b) heart c) large intestine d) small intestine

d) small intestine

What are the two characteristics of all radiation dose response relationships? a) linear or nonlinear, actual or hypothetical b) high or low radiation dose, immediate or delayed response c) threshold or nonthreshold, high or low radiation dose d) threshold or nonthreshold, linear or nonlinear

d) threshold or nonthreshold, linear or nonlinear

true/false: If cells that are needed to clot blood are depleted, the risk of hemorrhage decreases

false

true/false: early somatic effects occur within a long period of time after exposure to ionizing radiation

false

true/false: radiation exposure causes an increase in the number of red cells, white cells, and platelets in the circulating blood

false

true/false: Chromosomal damage can be caused by both high and low radiation doses

true

true/false: If the effects of ionizing radiation are cell-killing and directly related to the dose received, they are called nonstochastic (deterministic) somatic effects

true

true/false: In the human female a gonadal dose of 0.1 Gy (10 rad) may delay or suppress menstruation

true