Final - All chapters Flashcards

1
Q

In the presence of oxygen, the _________ effect is amplified with _______ LET radiation.

A

indirect, low

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2
Q

Which of the following is true regarding the multi-target model of cell lethality?

a. The critical target is considered to be the cells RNA.
b. Cells have more than one critical target, each of which has to be inactivated for cell death to occur.
c. The cell can accumulate radiation dose.
d. Only cell death can be measured with accuracy.

A

Cells have more than one critical target, each of which has to be inactivated for cell death to occur.

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3
Q

Which of the following statement(s) is/are true about target theory?

The key sensitive target molecule is DNA.
Hits occur only by indirect effect.
Radiation interaction with the targets is random.

A

1 & 3

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4
Q

Which of the following phases of the cell cycle is considered most radioresistant?
a. M phase
b. late S phase
c. G1 phase
d. I phase

A

late S phase

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5
Q

Irradiating human cells with a high LET radiation follows which model?

A

Single target, single hit

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6
Q

T/F: The lethal effects of cell irradiation are measured by cell death.

A

False
Measured by cell survival

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7
Q

Oxygen would enhance the effects of which type of radiation the most?

A

xray

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8
Q

When irradiated with x rays, human cells follow which model?

A

Multi-target, single-hit model

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9
Q

T/F: The effect oxygen has on high LET radiation is considered irrelevant.

A

True

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10
Q

This term is related to a cell’s capacity to recover from a sublethal dose.

A

DQ

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11
Q

This term is referred to as the threshold dose.

A

DQ

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12
Q

This term is represented by the width of the shoulder on a multi-target, single-hit curve.

A

DQ

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13
Q

This term is the dose necessary to reduce the survival rate of a cell population to the equivalent of D37.

A

D0

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14
Q

This term is a statistical measure that refers to a radiation dose level sufficient enough to kill 63% of cells in a population.

A

D37

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15
Q

This term is constant to cell radiosensitivity.

A

D0

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16
Q

This term is also known as the mean lethal dose.

A

D0

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17
Q

T/F: Grenz rays were a type of x-ray that were used to treat cancer.

A

False

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18
Q

What is the SED50 for humans?

A

5 Gy

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19
Q

T/F: The latent period occurs right after an acute exposure to radiation.

A

False

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20
Q

This type of multi-hit chromosome aberration occurs when adjacent chromosomes suffer one hit each and recombine with each other:

A

Dicentric

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21
Q

T/F: The LD50/30 is the amount of radiation to kill 30% of the population in 50 days.

A

False

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22
Q

T/F: Isochromatids are the least common type of single-hit aberration.

A

True

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23
Q

Which of the following is not a type of acute radiation sickness:

a. Hematologic syndrome
b. CNS syndrome
c. Hematopoietic syndrome
d. GI syndrome

A

c. Hematopoietic syndrome

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24
Q

Another name for deterministic effects is:

A

nonstochastic

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25
This mean survival time for which type(s) of acute radiation syndrome is dose dependent: Hematologic syndrome Gastrointestinal syndrome Central Nervous System syndrome
1 & 3
26
Ovaries and testes respond differently to radiation exposure because of:
gametogenesis
27
T/F: A dose of 5 Gy to the testes would result in temporary sterility.
False
28
________ desquamation is considered the clinical tolerance for radiation therapy.
Moist
29
T/F: Acute radiation lethality follows a non-linear, threshold curve.
True
30
What is the correct order in which the following will occur after an acute exposure to radiation: Manifest Illness Prodromal period Latent period
2 3 1
31
T/F: Multi-hit chromosome aberrations are observed at rapidly increasing levels in exposures greater than 1 Gy.
True
32
Erythrocytes are _________ sensitive to radiation because of their longer life span.
less
33
What is the LD50/60 for humans:
3.5 Gy
34
In which of the following multi-hit chromosome aberration is DNA actually re-arranged: a. Ring b. Dicentric c. Reciprocal Translocation d. Separation of Bases
c. Reciprocal Translocation
35
T/F: Lymphocytes are the human cell type that is most commonly used for cytogenic analysis.
True
36
Requires a dose of .01 Gy
Delay of Menstruation
37
Requires a dose of 10 to 50 Gy
G.I. Syndrome
38
Requires a dose of 2 to 10 Gy
Hematologic Syndrome
39
Has a mean survival time that remains constant
G.I. Syndrome
40
Requires a dose of 5 Gy
Permanent Sterility
41
Requires a dose of > 50 Gy
CNS Syndrome
42
T/F: The diagnostic beam always results in whole body exposure.
False
43
The two most radiosensitive cells are:
lymphocytes and spermatogonia
44
Multi-hit chromosome aberrations follow which dose response curve:
non-linear, non- threshold
45
Which of the following is the most radiosensitive period for a fetus?
1st trimester
46
What is the latent period for radiation-induced leukemia?
4 - 7 years
47
The latent period range for radiation induced cataracts is?
5 - 30 years, with an average of 15 years
48
The BEIR committee concluded that less than _____ may not be harmful.
0.1 Gy/yr
49
Radium watch dial painters in the 1920s and 1930s demonstrated which type of cancer?
Bone
50
Cataracts follow which type of dose response relationship?
nonlinear, threshold
51
The amount of radiation exposure that causes twice the frequency of a genetic mutation in a population is called?
Doubling Dose
52
In which of the following populations has Leukemia been observed: 1.Radiologists 2.Ankylosing Spondylitis Patients 3.TB Patients
1 & 2
53
Which of the following terms describes radiation damage which increases the probability of causing a late effect, but will not increase the severity of the effect? a. Non-stochastic b. Congenital c. Chronic d. Stochastic
d. Stochastic
54
A fetus receives .02 Gy of radiation exposure during the first two weeks of gestation and a spontaneous abortion did not result. What would the most likely response would be?
Nothing
55
What is the minimum radiation dose below which no genetic or cancer effects would occur?
No such levels
56
Radiation induced skin cancer follows a ___________ dose response relationship.
threshold
57
What is the best estimate for radiation-induced life-span shortening?
10 days/0.01 Gy
58
Miners developed lung cancer after being exposed to which type of radiation?
Radon
59
T/F: Radiation induced mutations are recessive.
True
60
T/F: Liver cancer was observed in patients that received Conray, a contrast agent used in angiography studies.
False
61
T/F: There is strong evidence that links radiation exposure to genetic effects in humans.
False
62
Radiation-induced leukemia follows a _________, ________ dose response curve.
linear, non-threshold
63
Which of the following statements regarding stochastic effects is false? a. They are also known as late term effects. b. They follow a linear, threshold dose response curve. c. They are chronic in nature. d. All the statements are false.
b. They follow a linear, threshold dose response curve.
64
The difference between observed cases and expected cases best defines:
Excess risk
65
If a technologist is exposed to 4 mGy/hr for 45 minutes during a fluoroscopy exam, what will her total exposure be?
3 mGy
66
The NCRP is the:
National Council of Radiation Protection
67
When using the inverse square law during fluoroscopy, the patient should be considered a/an _____________ source of radiation.
point
68
Exposure is measured by multiplying ______________ by ________________.
exposure rate, exposure time
69
The best approach to manage occupational radiation exposure is to:
Follow the concept of ALARA
70
T/F: Effective dose is the equivalent to whole-body dose.
True
71
The first radiation health physicists worked with:
the atom bomb
72
T/F: Dose to an individual is directly related to technique used, not to duration of exposure.
False
73
Health physics is concerned with minimizing radiation dose to: a. radiation physicists b. all of the above c. the public d. radiation workers
b. all of the above
74
T/F: TVL is defined as the thickness of absorber that reduces radiation intensity to 1/8th its original value.
False
75
If a technologist is receiving2 mGy/hr standing 1 foot from the patient during fluoroscopy what is his rate of exposure when he steps back to a; distance of 2 feet from the patient?
.50 mGy/hr
76
The three cardinal principals of radiation protection involve:
time, distance and shielding
77
T/F: he concept of effective dose accounts for the relative radiosensitivity of various tissues and organs.
True
78
T/F: Equivalent whole-body dose is the weighted average of the radiation dose to various organs and tissues.
True
79
The assumed constant Kilovolt Peak for diagnostic imaging is?
100kVp
80
How tall must primary protective barriers be?
7'
81
The maximum variation in linearity is +/-:
10%
82
Reproducibility of output intensity should be accurate to within +/-:
5%
83
T/F: The quality control area of an imaging department would be considered an uncontrolled area:
False
84
The exposure switch for portable x-ray machines should be on a cord that is at least ________ long.
1.8 m (6’)
85
Radiologic Technologists receive: most of their occupational dose from:
fluoroscopic exams
86
The light localized variable aperture collimator must be accurate to within +/-:
2% of the SID.
87
Which type of dosimeter uses Lithium Fluoride (LiF) as its phosphor?
Thermoluminescent Dosimeter (TLD)
88
Primary protective barriers must consist of ______ “ of lead or _____ “ of masonry:
1/16 4
89
T/F: The two types of primary radiation are scatter and leakage.
False
90
T/F: In fluoroscopy, the x-ray beam intensity at the tabletop should not exceed 2.1 mR/min for each mA of operation at 80 kVp
True
91
The bucky slot cover should have a total lead equivalent of:
.25mm
92
T/F: A secondary barrier always has a use factor (U) of 1:
True
93
A cumulative timer in fluoroscopy should produce an audible or visual signal when _______ of cumulative beam on time has been reached.
5 mins
94
Which of the following is not considered a type of gas-filled detector? a. proportional counter b. scintillation detector c. Geiger-Muller counter d. ionization chamber
b. scintillation detector
95
The level of radiation activity of a room best defines:
workload
96
The protective tube housing keeps leakage radiation to less than:
1 mGy/hr at 1 meter
97
The minimum SSD for stationary fluoroscopy is:
15"
98
Which of the following fall under the “frequent” level of occupancy? 1. corridors 2. work areas 3. waiting rooms 4. restrooms
1 and 4 only
99
The minimum amount of filtration for fluoroscopy is:
2.5 mm Al eq.
100
T/F: An optically stimulated luminescence (OSL) dosimeter can detect radiation doses as low as 1 mrem.
True
101
The most common way to report patient dose from diagnostic x-rays is:
entrance skin exposure
102
Medical imaging that captures the remnant beam to produce the image is now termed:
projection imaging
103
T/F: Mean Marrow Dose levels for children are higher than that of adults.
False
104
T/F: Alternate nonionizing modalities should only be an option when the dealing with a pregnant patient.
False
105
T/F: Mean Marrow Dose is a concept used to estimate the risk of radiation induced leukemia in a population.
True
106
Any time a patient receives a skin dose exceeding ___ Gy, it is referred to as a sentinel event and must be reported.
15
107
The type of radiation monitor most frequently used to measure patient exposure is the:
TLD
108
For the average fluoroscopy exam, the ESE is:
40 mGy/min
109
Which method of ESD measurement uses a family of curves to estimate patient exposure:
nomogram
110
Which of the following are ways in which patient dose may be expressed: 1. Bone Marrow Dose 2. Entrance Skin Exposure 3. Gonadal Dose 4.Tissue Dose
111
In the U.S. the Genetically Significant Dose from diagnostic x-ray is:
0.2 mGy/yr
112
T/F: Digital Radiographic Tomosynthesis can take 6-10 exposures with approximately the same patient dose as a single digital radiograph.
True
113
Which of the following is the easiest measure of patient dose to estimate:
entrance skin exposure
114
T/F: Bone marrow dose cannot be measured and is estimated from ESE.
True
115
The average ESD per view for mammography is:
8 mGy/view
116
Which of the following are reasons that extremity radiography is not a high radiation dose concern: No gonadal exposure Use of low technique Minimal contribution to MMD
1, 2, & 3
117
In order to reduce patient dose, we should use the ___ kVp, ___ mAs, and the ___ screen speed.
highest, lowest, fastest
118
The 100-250 Gy Rule applies to:
the unknowingly pregnant patient
119
A .5mm Pb shield will reduce a 75 kVp beam by:
88%
120
T/F: Shielding should only be utilized for patients that are of childbearing years.
False
121
In contact mammography, the ESE should not exceed _______ mGy per view.
1mGy
122
T/F: In order to elicit a fetal response to radiation, the fetal dose must be above 250 mGy.
True
123
The ACR Appropriateness Criteria is based on:
effective dose
124
All of the following are particularly sensitive organs that require shielding when in or near the primary beam except the: A. breast tissue B. thymus gland C. lens of the eye D. gonads
B. thymus gland
125
By positioning a patient PA, we reduce the dose to the breast tissue to approximately ________ of the AP projection
1%
126
The NCRP has determined that medical dose to the average US citizen has increased to ___ mSv per year.
3.2
127
As technologists, we should shoot for a repeat rate no higher than:
5%
128
Glandular Dose in Mammography is estimated to be ______ of the ESD.
15%
129
The high dose effect that would occur at a dose of 2 to 6 Gy is the: a. Hematologic Syndrome b. Gastrointestinal Syndrome c. Central Nervous Syndrome d. Prodromal Stage
a. Hematologic Syndrome
130
The most radioresistant phase of the cell cycle is: a. Interphase b. Mitosis c. DNA Replication d. Gap 1
c. DNA Replication
131
According to Target Theory: a. Only direct effects can cause hits b. RNA is considered the target molecule c. Only indirect effects can cause hits d. DNA is considered the target molecule
d. DNA is considered the target molecule d. Amino Acids
132
Of the following, which are considered the “Building Blocks” of protein synthesis? a. Chromatin b. Lipids c. Carbohydrates d. Amino Acids
d. Amino Acids
133
In a DNA molecule, the sequence of __________ determines the characteristics of every organism. a. Sugars b. Base Pairs c. Phosphates d. Hydrogen bonds
b. Base Pairs
134
Which of the following tissues is most radioresistant: a. Lymph b. Nerve c. Skin d. Thyroid
b. Nerve
135
Why is free radical formation considered such a threat to humans? a. Free radicals produce scatter radiation b. Free radicals can penetrate any type of shielding c. Free radicals have been proven to have carcinogenic effects d. Free radicals have been observed to produce toxic effects
d. Free radicals have been observed to produce toxic effects
136
Which of the following would be considered the most radio-resistant? a. A fetus b. A teenager c. An adult d. An elderly person
c. An adult
137
The target theory states that if ionization occurs in or near a key molecule, a. enzymes and proteins will be irreparably damaged b. Restitution is still highly likely c. DNA may be inactivated and the cell will die d. Two ion pairs will be produced
c. DNA may be inactivated and the cell will die
138
The term Epilation is used to refer to: a. Loss of hair b. Reduced white blood cell count c. Cataract formation d. Reddening of the skin
a. Loss of hair
139
Immature Somatic Cells are called: a. Genetic cells b. Base Cells c. Stem Cells d. Germ Cells
c. Stem Cells
140
The skin erythema dose (SED50) for humans is approximately: a. 0.5Gy b. 1Gy c. 3Gy d. 5Gy
d. 5Gy
141
What does the term “Indirect effect” of ionizing radiation refer to? a. Genetic effects are produced b. The ionizing event happens on the key target molecule c. Scatter radiation is produced d. The ionizing event occurs at one location and produces effects at a distant location
d. The ionizing event occurs at one location and produces effects at a distant location
142
How many matched pairs of chromosomes does a normal human cell contain? a. 13 b. 23 c. 26 d. 46
b. 23
143
The technical term for the division of genetic cells is: a. Mitosis b. Interphase c. Reproduction d. Meiosis
d. Meiosis
144
Which of the following describes the shape of a DNA molecule? a. Ovoid b. Double Helix c. Single Helix d. Spherical
b. Double Helix
145
Which of the following physiological effects are associated with and most likely to occur as a result of a patient who is a victim of the hematologic syndrome of acute radiation syndrome? a. Thrombus formation and remission b. headaches and coma c. Nausea and bloody diarrhea d. Decreased leukocytes and thrombocytes
d. Decreased leukocytes and thrombocytes
146
Which of the following cell groups are considered highly radiosensitive? a. Lymphocytes, spermatogonia, erythroblasts, and intestinal crypt cells b. Muscle cells, nerve cells, and chondrocytes c. Endothelial cells, osteoblasts, spermatids, and fibroblasts d. Muscle cells and osteoblasts
a. Lymphocytes, spermatogonia, erythroblasts, and intestinal crypt cells
147
Which action of ionizing radiation is most harmful to the human body? a. Indirect effect b. Direct effect c. Mitotic effect d. Double effect
a. Indirect effect
148
There is a high probability that a radiation hit will produce chromatid deletion in both arms of the chromosome: a. True b. False
b. False
149
Which of the following types of radiation has the highest Linear Energy Transfer (LET)? a. Gamma Rays b. Alpha Particles c. 1 MeV Electrons d. Fast Neutrons
b. Alpha Particles
150
The DQ in the cell survival curve describes the: a. Number of targets actually hit b. Organelle Damage c. DNA Damage d. Threshold dose of the irradiated cells
d. Threshold dose of the irradiated cells
151
The most radiosensitive part of the cell cycle is the ________ Phase. a. S b. G1 c. M d. G2
c. M
152
The least radiosensitive part of the cell cycle is the _______ phase. a. S b. G1 c. M d. G2
a. S
153
As radiation dose increases, the severity of deterministic effects is not effected. a. True B. False
B. False
154
At low doses of radiation, most cellular damage is the result of: a. Main-chain scission b. Cross-linking c. Point Lesions d. Cell Death
c. Point Lesions
155
DNA duplication occurs during which phase of the cell cycle? a. Prophase b. Mitosis c. Anaphase d. S Phase
d. S Phase
156
How does the LET of radiation affect its relative biologic effectiveness (RBE)? a. Higher LET Radiations have higher RBE values b. Higher LET radiations have lower RBE values c. Higher LET radiations cause RBE values to stabilize d. There is no correlation between LET and RBE
a. Higher LET Radiations have higher RBE values
157
The type of irradiation damage most likely to cause abnormalities in base sequences, and thus cell mutation, would be: a. Single-Strand breaks b. Cross-Linking c. Double-Strand Breaks d. Base Damage
d. Base Damage
158
What is the name of the molecule that has one or more unpaired electrons and is usually chemically reactive? a. Ion b. Polypeptide c. Amino acid d. Free Radical
d. Free Radical
159
The process of genetic cell division is called: a. Mitosis b. Synthesis c. Meiosis d. Reproduction
c. Meiosis
160
Which stage of the cell cycle is known as the “Resting Stage”? a. Prophase b. Mitosis c. Meiosis d. Interphase
d. Interphase
161
The dose to produce temporary epilation to the scalp is approximately: a. 0.5 Gy b. 1 Gy c. 3 Gy d. 7 Gy
c. 3 Gy
162
It is assumed that biological effects from diagnostic radiology exposures follow the ______________ dose-response model. a. Linear Threshold b. Linear Non-threshold c. Nonlinear Threshold d. Nonlinear Non-threshold
b. Linear Non-threshold
163
The Least radio-resistant cells in the human body are: a. epithelial cells b. Nerve Cells c. Osteocytes d. Lymphocytes
d. Lymphocytes
164
The Law of Bergonie and Tribondeau states that: 1. Younger cells are more radiosensitive 2. Rapidly dividing cells are more radiosensitive 3. Mature cells are less radiosensitive 4. Rapidly growing cells are more radiosensitive a. 1 and 2 b. 1, 2, and 4 c. 1, 3, and 4 d. 1, 2, 3, and 4
d. 1, 2, 3, and 4
165
Which of the following measures the rate of energy lost along the track of an ionizing particle? a. Relative Biologic effectiveness b. Linear energy transfer c. Oxygen enhancement Ratio d. Cell survival curve
b. Linear energy transfer
166
The term interphase death means: a. Cells die prior to entering interphase b. Cells die while replicating c. Cells die in between mitotic phases d. The organism dies
c. Cells die in between mitotic phases
167
The lethal dose of ionizing radiation for humans is usually given as follows: a. LD 50/30 b. LD 50/60 c. LD 30/90 d. LD0
b. LD 50/60
168
Meiosis is also known as the process of: a. Gametal division b. Reduction division c. Selective division d. Reproduction division
b. Reduction division
169
Which of following is the term used to describe the separation of water into hydrogen and oxygen following irradiation? a. Synthesis b. radiolysis c. Radiothesis d. Free radical production
b. radiolysis
170
The LD 50/60 dose to the whole body with no medical support is approximately: a. 0.5 Gy b. 1 Gy c. 3.5 Gy d. 6 Gy
c. 3.5 Gy
171
Water constitutes approximately ____% of the body. a. 60 b. 75 c. 80 d. 90
c. 80
172
If a DNA base sequence is altered, which of the following would occur? a. Gene Mutation b. Gene duplication c. Gene replication d. Formation of chromatin
a. Gene Mutation
173
In mitosis, chromosomes split into two halves. These halves are called? a. Centromeres b. Chromatids c. Sister chromosomes d. isochromatids
b. Chromatids
174
The process of cell division of reproductive germ cells is called: a. Meiosis b. Mitosis c. Transcription d. Synthesis
a. Meiosis
175
The stage of high-dose radiation effects in which the individual appears to have recovered but may still exhibit symptoms at a later date is called the: a. Prodromal stage b.Latent Period c. Manifest Illness d. Recovery Stage
b.Latent Period
176
Relative Biologic Effectiveness (RBE): a. Describes a measure of the rate at which energy is deposited as a charged particle travels through matter b. Is a quantitative value of how much biologic damage radiation can cause c. Is defined as the dose of radiation that produces a given biologic response under anoxic conditions divided. by the dose of radiation that produces the same biologic response under aerobic conditions d. States that the stem cells are more radiosensitive than mature cells
b. Is a quantitative value of how much biologic damage radiation can cause
177
Which of the following measures the rate of energy lost along the track of an ionizing particle? a. Relative biologic effectiveness b. Linear energy transfer c. Cell survival curve d. Oxygen enhancement ratio
b. Linear energy transfer
178
The high dose effect that occurs at doses ranging from 2 Gy to 10 Gy is the: a. Central Nervous syndrome b. Prodromal Stage c. Hematologic Syndrome d. Gastrointestinal Syndromec.
c. Hematologic Syndrome
179
The _______ is the first stage in acute radiation syndrome: a. Latent period b. Prodromal period c. Manifest illness d. Recovery
b. Prodromal period
180
Which of the following terms is used in describing cell damage from radiation that is not sufficient to kill the cell? a. Interphase recovery b. Interphase damage c. Sublethal recovery d. Sublethal damage
d. Sublethal damage
181
Which of the following body molecules are most commonly acted upon directly by ionizing radiation to produce indirect effects? a. Lipids b. Proteins c. Carbohydrates d. Water
d. Water
182
Higher acute doses will result in ____ latent periods: a. Shorter b. Longer c. Unchanged d. None of the above
a. Shorter
183
The types of DNA molecule damage include: 1. Main-chain scission, one side rail broken 2. Main-chain scission, both side rails broken 3. Main-chain scission, resulting in cross-linking 4. Rung breakage, cause bases to separate 5. A change in or loss of a base a. 4 only b. 1, 2, and 3 c. 1, 2, 4 and 5 d. 1, 2, 3, 4, and 5 e. None of the above
d. 1, 2, 3, 4, and 5
184
Which of the following contains the human hereditary blue print? a. The nucleolus b. RNA c. Ribosomes d. Genes
d. Genes
185
Which of the following systems is the most radiosensitive vital organ system in human beings? a. Reproductive b. skeletal c. Gastrointestinal d. Hematopoietic
d. Hematopoietic
186
In which area of the cell is the majority of RNA located? a. Nucleolus b. Mitochondria c. Lysosomes d. Cytoplasm
d. Cytoplasm
187
Nonthreshold: a. Means that an observed response is directly proportional to the dose b. Means that an observed response is not directly proportional to dose c. Assumes that there is a radiation level reached under which there would be no effects observed d. Assumes that any radiation dose produces an effect
d. Assumes that any radiation dose produces an effect
188
How does oxygen retention affect cell radiosensitivity? a. Increases radiosensitivity b. Decreases radiosensitivity c. Does not affect radiosensitivity d. Negates Radiosensitivity
a. Increases radiosensitivity
189
In order for an indirect hit to occur, the initial ionizing event must happen to the DNA molecule. a. True b. False
b. False
190
Based upon the Law of Bergonie and Tribondeau, the fetus is highly radiosensitive because of: a. Low proliferation rates b. High Mitotic activity c. Large numbers of mature and highly differentiated cells d. Its environment
b. High Mitotic activity
191
There is a possibility of recovery from any acute radiation exposures. a. True b. False
b. False
192
Radiation induced chromosomes damage may be evaluated during which of the following phases? a. Prophase b. Metaphase c. Anaphase d. Telophase
b. Metaphase
193
Which of the following is (are) used to account for the differences in tissue sensitivity to ionizing radiation when determining the effective dose (E)? 1. tissue weighting factor 2. radiation weighting factor 3. absorbed dose
1, 2, & 3
194
According to the NRCP, the monthly gestational dose equivalent limit for the embryo/fetus of a pregnant radiographer is? a. .15mSv b. .5mSv c. .25 mSv d. .75mSv
b. 0.5mSv
195
What is the established annual occupational dose-equivalent for the lens of the eye? a. 5mSv b. 10mSv c. 50 mSv d. 150 mSv
d. 150 mSv
196
According to the NRCP, the annual occupational whole-body dose equivalent limit is? a. 1mSV b. 50mSv c. 150mSv d. 500mSv
b. 50mSv
197
An optically stimulated luminescent dosimeters contains which of the following detectors? a. gadolinium b. aluminum oxide c. lithium fluoride d. photographic film
b. aluminum oxide
198
Occupational radiation monitoring is required when it is possible that the individual might receive more than: a. 5mSv b. 10mSv c. 1/10th of the annual dose limit d. 1/th the annual dose limit
c. 1/10th of the annual dose limit
199
Which of the following is recommended for the pregnant radiographer? a. change dosimeters weekly. b. Wear a 2nd dosimeter under the lead apron at waist level c. Wear 2 dosimeters and switch their positions accordingly d. The pregnant radiographer must leave radiation areas for the duration of the pregnancy
b. Wear a 2nd dosimeter under the lead apron at waist level
200
According to the NCRP, the annual occupational dose equivalent to the thyroid skin and hands and feet is: a. 50mSv b. 150mSv c. 500mSv d. 1500mSv
c. 500mSv
201
Which of the following personnel monitoring devices used in diagnostic radiography is considered to be the most sensitive and accurate? a. TLD b. Film badge c. OSL d. Pocket dosimeter
c. OSL
202
Which of the following are true regarding TLD's? 1. They are reusable 2. It can measure doses as low as 1mrem 3. It uses a lithium fluoride crystal a. 1 only b. 2 only c. 1 & 3 only d. 2 & 3 only e. 1, 2, & 3
c. 1 & 3 only
203
The % of x-ray attenuation at 100 kVp with a .5 mmPb apron is? a. 66% b. 51% c. 75% d. 99%
c. 75%
204
What is the radiation weighting factor for energy levels ranging from 2Mev-20MeV? a. 1 b. 5 c. 10 d. 20
c. 10
205
The standard radiation monitoring device should be worn? a. Outside the apron, chest level b. Inside the apron, chest level c. Outside the apron, waist level d. Inside the apron, waist level
a. Outside the apron, chest level
206
Protective apparel must be a minimum of how many mm of Pb? a. .25 b. .5’ c. 1 d. None of the above
a. .25
207
Which of the following lead to higher dose levels for occupational workers? 1. Longer beam on time in fluoroscopy 2. low kVp used in mammography 3. finely collimated beam in CT a. 1 only b. 1 & 3 only c. 1 & 2 only d. 1, 2, & 3
208
Which of the following tissues types does not have a weighting factor of .05? a. bladder b. breast c. liver d. gonads
d. gonads
209
Dose limits are based on the ____ dose response relationship. a. linear, threshold b. linear, nonthreshold c. nonlinear, threshold d. nonlinear, nonthreshold
b. linear, nonthreshold