Final test 4-7 Flashcards
Who was the first American radiation worker to die from radiation-induced cancer in October of 1904?
Clarence Madison Dally
Which of the following are early tissue reactions of ionizing radiation that were experienced by early radiation workers?
1. Diffuse redness of skin
2. Blood disorders
3. Organ atrophy
4. Intestinal disorders
1,2, and 4
0.2 Gy equals
200 mGy
The total kinetic energy released in a unit mass (kilogram) of air and expressed in metric units of joules per kilogram is
air kerma
Which of the following is essentially the sum total of air kerma over the exposed area of the patient’s body surface?
Dose area product
The whole-body TEDE regulatory limit for exposed personnel is _____________ and ______________ for the general public.
0.05Sv; 0.0001 Sv
As the intensity of x-ray exposure of the air volume increases, the number of electron–ion pairs produced
also increases
What do radiation weighting factors take into consideration?
-the overall risk of exposure to humans from ionizing radiation
-both the internal and external dose measurments
-the fact that some types of radiation are more efficient at causing biologic damage than other types of radiation for a given dose
1 gray equals
100 cGy
In the SI system, an energy absorption of 1 J/kg of matter in the irradiated object equals which of the following?
1 Gy
Cataract formation, fibrosis, reduced fertility, and sterility are classified as
late tissue reactions of ionizing radiation
Which of the following types of ionizing radiation produce virtually the same biologic effect in body tissue for equal absorbed doses?
X-rays, beta particles, and gamma rays
What theory relates the ionization produced in a small cavity within an irradiated medium or object to the energy absorbed in that medium as a result of its radiation exposure?
Bragg-Gray
If 400 people receive an average effective dose of 0.25 Sv, what is the collective effective dose?
100 person-sv
For x-ray and gamma ray photons with energies up to 3 million electron volts (MeV), which of the following radiation quantities may be defined as the measure of the total electrical charge of one sign, either all pluses or all minuses, per unit mass that these two types of radiation generate in dry air (i.e., nonhumid) at standard temperature and pressure (760 mm Hg or 1 atmosphere at sea level and 22° C)?
Exposure
Which of the following formulas is used to calculate effective dose?
EfD = D × WR × WT
Alpha particles have a radiation weighting factor (WR) that is numerically equal to
20
Which of the following units of measure are not SI units?
Roentgens and rads and rems
How is dose area product usually specified?
In units of mGy-cm2
What instrument can be calibrated to read air kerma?
Standard, or free-air, ionization chamber
Which of the following is the SI unit of electrical current?
Ampere
Which of the following is the SI unit of electrical current?
high-speed electrons
Among physicians, cancer deaths attributed to x-ray exposure were reported as early as
1910
Among physicians, cancer deaths attributed to x-ray exposure were reported as early as
Gray and centigray
Who discovered x-rays on November 8, 1895?
Wilhelm Conrad Roentgen
Three different filters are incorporated into the detector packet of the optically stimulated luminescence dosimeter. Of what are these filters made?
Aluminum, tin, and copper
What is the maximum period of time that a thermoluminescent ring dosimeter (TLD) may be worn as a personnel device?
3 months
What do optically stimulated luminescence dosimeters, thermoluminescent ring dosimeters, and personnel direct ion storage dosimeters have in common?
These devices are all used for personnel monitoring.
Which of the following instruments is called a cutie pie?
Ionization chamber-type survey meter
Which of the following instruments generally has a check source of a weak, long-lived radioisotope located on one side of its external surface to verify its constancy daily?
Geiger-Műller survey meter
Which of the following devices contains an aluminum oxide detector?
Optically stimulated luminescence dosimeter
When the sensing material contained in the thermoluminescent ring dosimeter is irradiated, which of the following occurs?
Some of the electrons in the crystalline lattice structure of the LiF molecule absorb energy and are excited to higher energy levels or bands.
Because of the OSL dosimeter’s sensitivity down to as low as 10 µSv for x-ray and gamma ray photons in the energy range 5 keV to 40 MeV, it is an excellent and practical monitoring device for
employees working in low-radiation environments and for pregnant workers.
The effective atomic number (Zeff) of lithium fluoride (LiF) is equal to
8.2
Which of the following are advantages of the personnel direct ion storage dosimeter?
1. Instant access to reports
2. No waiting time for mailing dosimeters
3. Lightweight and durable
4. Can be dropped or scratched with little chance of harm to the device
All options
How is the readout for a personnel direct ion storage dosimeter obtained?
Through a physical connecting device such as a universal serial bus (USB) or via wireless connection
Which of the following are disadvantages of the TLD ring dosimeter?
Thermoluminescence readings will be lost if not carefully recorded.
The readout process destroys information stored in the TLD ring dosimeter, thus preventing the “read” from serving as a permanent legal record of exposure.
Calibrated dosimeters must be prepared before-hand and read with each group of TLDs as they are processed.
Which component(s) of the Geiger-Muller survey meter alerts the operator to the presence of ionizing radiation?
An audio amplifier and speaker
Which of the following is not a requirement that radiation survey instruments must meet?
Correct!
They must all be equally sensitive in the detection of all types of ionizing radiation.
Medical physicists use ionization chambers, connected to electrometers to perform the annual standard measurements required by state, federal, and health care accreditation organizations for radiographic and fluoroscopic devices. These annual measurements include
1. x-ray output in Gy or mGy.
2. fluoroscopic radiation entrance rates in mSv/min or R/min.
3. kVp setting accuracy.
4. exposure time exactness.
5. half-value layers, or beam quality.
All options
When changing employment, what must a radiation worker convey to his/her new employer?
Data pertinent to accumulated permanent equivalent dose to be placed on file
The personnel direct ion storage dosimeter provides an instant read-out of dose information when connected to a computer via a connector such as a (an)
universal serial bus (USB).
The front of the white paper packet of the optically stimulated luminescence (OSL) dosimeter
Correct!
may be color coded to facilitate correct usage and placement of the dosimeter on the body of occupationally exposed personnel.
Three different filters are incorporated into the detector packet of the optically stimulated luminescence (OSL) dosimeter. These filters are respectively made of
1. aluminum.
2. copper.
3. molybdenum.
4. rhenium tungsten.
5. tin.
1, 2, and 5 only
An ionization chamber connected to an electrometer is a device that can measure
tiny electric currents with high precision and accuracy.
Which of the following personnel monitoring devices can be used to provide an immediate exposure readout for a radiation worker?
Correct!
Personnel direct ion storage dosimeter
Which of the following is a disadvantage of the optically stimulated luminescence dosimeter?
Correct!
Exposure not determinable on the day of occurrence without an in-house reader
Whenever the letter “M” appears under the current monitoring period or in the cumulative columns of a personnel monitoring report, it signifies that a (an)
equivalent dose below the minimum measurable radiation quantity was recorded during that time.
The optically stimulated luminescence (OSL) dosimeter is “read out” by using a (an)
laser light at selected frequencies.
Some of the advantages of the optically stimulated luminescence (OSL) dosimeter are
1. can be used for up to 1 year.
2. lightweight, durable, and easy to carry.
3. integrated, self-contained, preloaded packet.
All options
In general, which of the following can human cells do?
1. Move, grow, react, and protect themselves
2. Repair damage and regulate life processes
3. Reproduce
All options
Inorganic materials are compounds that
do not contain carbon.
Antibodies are protein molecules created by specialized cells in the bone marrow called
B lymphocytes.
The steps, or rungs, of the DNA ladder-like structure consist of complementary chemicals that are
pairs of nitrogenous bases.
Which of the following are compounds called purines?
Adenine and guanine
The much smaller structures that are building blocks of nucleic acids are called
nucleotides
Which of the following serves as a prototype for messenger RNA (mRNA)?
Deoxyribonucleic acid (DNA)
The cell components that contain the centrioles are the
centrosomes
What do the highly organized enzymes in the inner membranes of the mitochondria break down?
Carbohydrates
Fats
Proteins
During which of the following subphases of mitosis do the centrioles migrate to opposite sides of the cell and begin to regulate the formation of the mitotic spindle?
Prophase
In the human body mineral salts are necessary for
1. proper cell function.
2. creation of energy.
3. conduction of impulses along nerves.
All options
Which of the following can cause an increase in cellular activity that in turn causes biochemical reactions to occur more rapidly to meet the needs of the cell in stressful situations?
Enzymes
How many different amino acids are involved in protein synthesis in humans?
22
A nucleotide is formed from a nitrogen-containing organic base, a ________________ molecule, and a phosphate molecule.
five-carbon sugar
Cytosine bonds only with
guanine
Which of the following are major tasks of the cytoplasm?
1. Accepts and builds up unrefined materials and assembles from these materials new substances such as carbohydrates, lipids, and proteins.
2. Breaks down organic materials to produce energy.
3. Packages substances for distribution to other areas of the cell or to various sites in the body through the circulation.
4. Eliminates waste products.
All options
Which of the following is/are considered to be acellular tissue?
Hair and nails
Adenine bonds only with
thymine
What should the constant core temperature of the human body be?
57° C
Lysosomes are sometimes referred to as “suicide bags,” because their enzymes break down and digest not only proteins and certain carbohydrates but also will do the same to the cell itself should the lysosome’s surrounding membrane rupture. Exposure to radiation may induce such a rupture. When this occurs what will happen to the cell?
It is likely to die.
What is any chemical reaction in which atoms lose electrons called?
Oxidation
During mitosis, which phase of the cellular life cycle is the actual DNA synthesis period?
S
During what phase of mitosis are the centromeres severed followed by the sister chromatids moving apart and are then subsequently pulled toward opposite poles of the mitotic spindle?
Anaphase
What is a highly coiled strand that is one of two duplicated portions of DNA in a replicated chromosome that appears during cell division identified as?
A chromatid
Fraternal twins may also be referred to as
dizygotic twins.
A biologic reaction is produced by 4 Gyt of a test radiation. It takes 16 Gyt of 250-kVp x-rays to produce the same biologic reaction. What is the relative biologic effectiveness (RBE) of the test radiation?
4
Which of the following is/are considered low-LET radiation(s)?
X-rays and gamma rays
The radiation dose required to produce mitotic death is
less than the dose needed to produce apoptosis in slowly dividing cells or nondividing cells.
Because the genetic information to be passed on to future generations is contained in the strict sequence of nitrogenous bases, the loss or change of a base in the DNA chain represents a (an)
mutation
Because the master molecule is unique in any given cell, no similar molecules in the cell are available to replace it; if a critical location on the master molecule is a target receiving multiple hits from ionizing radiation, the master molecule may be inactivated. If this occurs, what is the consequence for the affected cell?
Normal cell function will cease, and the cell will die.
Which of the following curves illustrates the radiation sensitivity of a particular type of cell?
Cell survival curve
Which of the following groups of cells is least radiosensitive?
Adult nerve cells
OH* + OH*
H2O2
Which of the following humans is most radiosensitive?
An embryo-fetus during the first trimester of pregnancy
When free radicals previously produced by the interaction of radiation with water molecules act on a molecule such as DNA, the damaging action of ionizing radiation is indirect in the sense that the radiation is not the immediate cause of injury to the macromolecule. What is the immediate cause of this damage?
The free radicals produced by the interaction of radiation with water molecules
The normal white blood cell count for an adult ranges from
5000 to 10,000/mm3 of blood.
One micron (μm) = __________
10–6 m
A periodic blood count is not recommended as a method for monitoring occupational radiation exposure because
biologic damage has already been sustained when an irregularity is seen in the blood count.
a blood count is a relatively insensitive test that is unable to indicate doses of less than 10 cGyt accurately.
Based on current data, which of the following would be considered a safe radiation dose for the gonads of both males and females
0 Gyt
Which of the following statements is true concerning patients who receive radiation exposure from a routine radiographic procedure such as a chest x-ray?
Patients are not expected to sustain appreciable damage to either the blood or the blood-forming organs as a consequence of the examination.
The term apoptosis is synonymous with
programmed cell death.
Which of the following gonadal radiation doses may cause permanent sterility in a male human?
5.0 or 6.0 Gyt
Which of the following groups of cells is most radiosensitive?
Lymphocytes
Direct action may occur after exposure to any type of radiation, but it is much more likely to occur after exposure to
high-LET radiation such as alpha particles.
When LET increases, the chance of a significant biologic response in the radiosensitive DNA macromolecule
also increases.
Neutrophils play an essential role in
fighting infection.
The radiosensitivity of ova
varies considerably throughout the lifetime of the germ cell.
Which of the following tissues contain cells that do not divide?
1. Epithelial tissue
2. Muscle tissue
3. Nervous tissue in an adult
2 and 3 only
Which of the following is a category of white blood cell that is essential in fighting infections?
Granulocytes
If bone marrow cells have not been destroyed by exposure to ionizing radiation, they can
repopulate after a period of recovery.
