What is the period of growth of the cell between divisions?
interphase
What is the period of pre-DNA synthesis phase?
G1
What is the period of DNA synthesis phase?
S
What is the period of post-DNA synthesis phase?
G2
What is the process of somatic cell division where a parent cell divides to form two daughter cells, and is identical to the parent cell?
Mitosis
At what phase of mitosis are chromosomes able to seen under the microscope?
metaphase
What is the process of germ cell division that reduces the chromosomes in each daughter cell to half the number the of chromosomes in the parent cell?
meiosis
What type of cell goes through mitosis?
somatic cells
What type of cell goes through meiosis?
germ cells
Is there DNA replication in mitosis?
yes
Is there DNA replication in meiosis?
yes
How many divisions are in mitosis?
1 round
How many divisions are in meiosis?
2 rounds
How many daughter cells are in mitosis?
2 daughter cells
How many daughter cells are in meiosis?
4 daughter cells
In Mitosis, are the daughter cells identical or non-identical?
identical
In Meiosis, are the daughter cells identical or non-identical?
non-identical
Does crossing over occur in mitosis?
no
Does crossing over occur in meiosis?
yes
What is a very large molecule consisting of thousands of atoms?
macromolecule
What are 4 examples of macromolecules?
1. proteins
2. lipids
3. carbohydrates
4. nucleic acids
What is the chief function of carbs?
provides fuel for cell metabolism
What is the chief function of lipids?
Provide fuel for the human body and thermal insulation
What does proteins function as?
muscles and provide support/structure
What are the 3 important things that proteins functions as?
enzymes, hormones, and antibodies
What allows biochemical reactions to occur in the body?
enzymes
What is responsible for growth and development?
hormones
What is the body's defense against infection and disease?
antibodies
The body consists of 15% of what?
proteins
What 2 types of interaction that occur in diagnostic radiology are radiographers most concerned with?
Photoelectric Effect & Compton Scatter(Recoil Electron Effect)
What occurs when body tissue totally absorb ionizing radiation?
Photoelectric Effect
What is responsible for contrast?
Photoelectric Effect
What has x-ray energy greater than or equal to binding energy of k-shell electrons?
Photoelectric Effect
What is the primary source of radiation to the patient?
Photoelectric Effect
What is it called when a xray/photon is partially absorbed, knocking out an "outer" shell electron?
Compton Scatter/Recoil Electron Effect
What predominates between 80kev -150kve?
Compton Scatter/Recoil Electron Effect
What causes 99% of all scatter radiation?
Compton Scatter/Recoil Electron Effect
What reduces contrast?
Compton Scatter/Recoil Electron Effect
What is the reason why we use buckys?
Compton Scatter/Recoil Electron Effect
What is the primary source of radiation to the tech?
Compton Scatter/Recoil Electron Effect
What has higher energy going in and lower energy coming out (change in wavelength)?
Compton Scatter/Recoil Electron Effect
What has no effect on Compton Scatter/Recoil Electron Effect ?
Atomic number
What is located in the nucleus of the cell?
DNA
What is the command or control molecule for cell function?
DNA
What contains all hereditary information representing a cell?
DNA
What is everything but the structures (the bulk) and site of metabolic structures?
Cytoplasm
What is the balancing act of catabolism and anabolism?
metabolism
What are the pipe-like system of membranes that occupy much of the cytoplasm?
Endoplasmic Reticulum
What allows the nucleus and cytoplasm to communicate?
Endoplasmic Reticulum
What looks like "dots" and is the site of protein-synthesis?
Ribosomes
What makes protein by reading messenger RNA?
Ribosomes
What is the power house/energy source for cellular functions?
Mitochondria
What digests macromolecules to produce energy?
Mitochondria
What is known as "recyclers" and is responsible for cellular digestion?
Lysosomes
What breaks down larger molecules or old proteins for reuse?
Lysosomes
What are the 2 cell classifications?
Germ & Somatic Cells
What type of cells consists of female(oognium) and male(spermatozonium) cells?
Germ cells
What type of cell starts at 23 chromosomes then fuse together to make 46 chromosomes?
Germ cells
What type of cell consists of all other types of cells?
Somatic cells
How many chromosomes are in Somatic cells?
23 chromosomes (26 pairs)
Which cell type is least sensitive to radiation?
muscle and nerve cells
Which cell types are most sensitive to radiation?
immature, undifferentiated, pre-curser, and stem cells
What does LET stand for?
Linear Energy Transfer
What is LET expressed in?
kilo-electron volts per soft tissue
What is a measure of the rate at which energy is transferred from ionizing radiation to soft tissue?
LET
What is responsible for radiation quality and weighting factor?
LET
What is the LET of diagnostic x-rays?
3 kev
What does RBE stand for?
Relative Biologic Effectiveness
What is the ratio of the dose of standard radiation to produce of given effect over a teat radiation to produce the same effect?
RBE
What is the RBE of diagnostic radiation?
1 kev
What is the relationship between LET and RBE?
directly proportional
What is the same dose given in equal portions at regular intravals?
Fractionation
What is the dose that is delievered continuously at a "low" dose rate?
Protraction
What is when biologic tissue is more sensitive to radiation when radiated in oxygenated aerobic state?
oxygen effect
What does OER stand for?
Oxygen Enhancement Ratio
What does OER mean?
Biologic tissue is more sensitive to radiation
What is the numerical representation of oxygen effect?
OER
OER is LET- independent or dependent?
dependent
As OER decreases, does LET increase or decrease?
increases
What bonds with adenine?
Thymine
What bonds with cytosine?
Guanine
Who and when named the cell the basic building block?
Robert Hooke, 1665
Who and when discovered the molecular structure of DNA in the cell?
Watson & Crick, 1953
What effect is usually early (minutes or days) and has a high exposures?
Deterministic Effect
What effect is usually late (months or years) and has a low exposures?
Stochastic Effects
The body contains 80% of what?
water
The body contains 2% of what?
lipids
Carbs and nucleic acids contains what percentage of the body?
0.01
What is the ratio of lipids?
1:3 (glycerol & fatty acid)
What is the ratio of carbs?
2:1 (hydrogen & oxygen)
What is the radiation-sensitive target molecule?
DNA
In what phase does the nucleus of the cell swell and DNA is prominate and takes shape?
Prophase
In what phase does chromosomes line up at the equator of the cell?
metaphase
At what phase can radiation be analyzed under a microscope?
metaphase
At what phase does chromosomes split because of spindal fibers and are pulled apart at the centromere?
anaphase
At what phase does the chromosomes appear as a mass of DNA and cytoplasm is divided into two equal parts?
Telophase
The two primary forms of diagnostic xray interaction in diagnostic range are what?
Compton scattering and photoelectric absorption
An outer-shell electron is ejected and the atom is ionized during what?
Compton interactions
Which xray interaction involves the ejection of the k-shell electron?
Photoelectric absorption
Compton scatter is directed at what angle from the incident beam?
any angle
As kVp___________, the probability of photoelectric absorption _____________.
increases, decreases
In _____________ , there is complete absorption of the incident xray photon.
Photoelectric interaction
What has the greatest mass density?
bone
Barium is a good contrast agent because of its what?
high atomic number
A negative contrast agent is what?
air
Xrays transmitted without interaction contribute to what?
beam attenuation
If 5% of an incident beam is transmitted through a body part, then 95% of that beam was ____________.
absorbed
Tungsten (symbol is W), has: 74 protons and 110 neutrons. What is the Z#?
74
The metabolic process of building large molecules from smaller ones is called:
Anabolism
DNA is located in the ______________ of the cell.
Nucleus
The two major parts of the cell are the nucleus and the ___________________.
cytoplasm
The _____________ have the function of cleaning contaminants from the cell.
Lysosomes
The most radiosensitive target molecule in the human cell is the ___________.
DNA
The _______________ in the cell are nucleic acids.
DNA and RNA
The human body is composed of about 80% of what?
water
The ____________ is the basic functional unit of all plants and animals.
cell
A cell is in ___________ when it is not undergoing mitosis and meiosis.
Interphase
Meiosis is the process of cell division for ___________ cells.
Germ
Ribonucleic acid (RNA) is located primarily in the _____________.
Cytoplasm
What does it mean to have no oxygen?
anoxic
What does it mean to have low oxygen?
hypoxic
What does it mean to be oxygenated?
aerobic
Tissue/organ shrinkage due to the death of some cells and the cell that dies gets carried away as waste is known as?
atrophy
What are agents that enhance the effect of radiation by ratio of 2?
Radiosensitive
What is not for use with humans, protective ratio of 2?
Radioprotectors
What is the response that is directly proportional to the dose (straight line)?
linear
What is varied doses that produce varied response?
Non-linear
What is a dose that is below a certain level that may produce no response?
Threshold
What is any dose that is expected to produce a response?
Non-threshold
What radiation dose-response is a zero on the axis?
Non-threshold
What radiation dose-response relationship is in diagnostic radiation?
linear : non-threshold
What happens when you double the dose?
double the response
What is the estimation of a value beyond the range of known values?
Extrapolation
What is the rarest type of macromolecules?
nucleic acids
On the sides of the DNA ladder what is alternating?
sugar and phosphate molecules
The two bases of the DNA rung of the ladder connects to what?
sugar molecule
RNA can be found where?
nucleoli
What is also known as reproductive cells?
germ cells
What is the process that can happen in metaphase and can exchange genetical material from the chromatids?
crossing-over
What cells are high radiosensitive?
reproductive cells
What is the reduction in total number of xrays and intensity?
attenuation
Different degrees in absorption in different tissues that result in image contrast and formation of the xray is known as?
Differential absorption
The Central Nervous System syndrome occurs following a whole body dose of _______ Gy or more.
50
What is the relationship like with dose and time?
direct
The disassociation of water molecules following irradiation is termed, what?
Radiolysis
The initial ionizing event of radiolysis produces two ions; they are:
HOH+ and e-
If time is doubled, what happens with dose?
doubles
Immediately following a whole body dose of 15Gy the victim would experience.
Prodromal symtoms
Irradiation hits occur through _______________.
indirect effects & direct effects
There is usually a _____ before the symptoms of acute radiation syndromes appear.
Latent Period
rate X time = ?
exposure
The most common interaction of radiation and DNA is a result of what type of effect?
indirect effect
What is the most common barrier used in shielding?
lead
A person subjected to 50Gy to the whole body may survive for _____ before death occurs.
3 Days
What is the dose quantity that accounts for different types of radiation and the radiosensitivity of various tissue and organs?
effective dose (E)
During the Latent period, the radiated victim experiences.
well-being
The free radicals produced during radiolysis of what are:
H
and OH
Diagnostic tube housing must be shielded so that radiation leakage may not exceed _______________ at 1 meter.
1 mGya/hr
Death from acute radiation exposure follows a _______, _______ dose-response relationship.
nonlinear, threshold
The principal radiation interaction within the human body is with, what?
water
Protective gloves worn MUST have a Pb equivalent of:
0.25mm
What is the first state of the acute radiation syndrome which occurs within minutes/ hours after radiation exposure (lasts a day or two)?
prodromal period
If the dose equal to D37 were distributed, what percentage of cells would survive?
0.37
Scatter to the radiologic technologist during fluoroscopy is primarily caused by:
the patient
What has a total body radiation doses above 1Gyt?
prodromal period
When an atom of water is irradiated if first dissociates into ___________.
an ion pair
Two OH* free radicals can join to form ____________ molecules.
hydrogen peroxide
What has the symptoms of nausea, vomiting, diarrhea, and reduction in white blood cells?
prodromal period
Regarding an aluminum filter used in the beam of a diagnostic x-ray machine. What is its purpose?
to reduce low energy x-rays and reduce patient dose & scatter
Total filtration = ?
inherent plus added
What is the period after prodromal stage where there is no visible sign of radiation sickness?
latent period
Free radicals can be damaging because they are ________________.
unstable & highly reactive
Primary protective barrier must have a lead equivalency of at least:
4 inches of masenry is equivalent to 1/16in of lead
What extends from hours (or less) at doses in excess of 50Gyt, and up to weeks at doses from 1-5Gyt?
latent period
An indirect effect from ionizing radiation occurs on a ______________ molecule.
water
The thickness of the protective barrier depends on what?
the distance between the source of radiation and the barrier
What period has no symptoms?
latent period
Ionizing events from irradiation are considered to be direct effects of they occur with ____________.
DNA
What are the 6 factors regarding the thickness protective barrier?
1. distance
2. occupancy factor
3. control
4. workload
5. risk factor
6. kVp
What was the first development of radiation induced cataracts caused by? Who did it effect?
Physicists working on old cyclotrons staring directly into the radiation.
Radiation reacts randomly with, what?
tissues
What is the thickness of a solution?
Viscosity
What is the purpose of the bucky slot cover/protective drape on a R & F radiographic machine?
to cover the opening left by the movement of the bucky tray
Which trimester is most sensitive to radiation?
1st
What is the reduction in blood cells?
hematological death
The 0.25mm lead of the protective drape on the fluoroscopy machine protects what level for occupational workers?
gonadal level
What is an example of a low viscosity?
water or juice
What death is associated with 2-10Gyt (200-1000 rad)?
hematological death
What is an example of high viscosity?
maple syrup or pudding
What equipment has a dead man switch for radiation?
fluoroscopy
What is the minimal thickness of the protective curtain between the fluoroscope and the operator?
at least 0.25mm
What syndrome is the only one you can survive from?
hematological death
What is the term that means outside of the body and is more resistant to radiation damage?
In-vitro
A cumulative timer that produces an audible signal but temporally interrupts the x-ray beam?
timer in fluoro
If dose is not lethal, recovery begins in 2-4 weeks and extends for 6 months for full recovery is describing what syndrome?
hematological death
What is the term that means inside of the body and is more radiosensitive in a natural state?
Vitro
A fluoroscopic machine cannot exceed time no more than?
5 minutes
What can cause electrolyte imbalance and dehydration causing death within 10-60 days?
hematological death
The radiation effect is reversible through what?
introcellular repair/recovery
What is damage to intestinal lining?
gastrointestinal (GI) death
What is the reduction of a long single molecule into many smaller molecules?
main-chain scission
What are the 2 types of secondary radiation?
scatter and leakage
What death is associated with 10-50Gyt (100-5000rad)?
gastrointestinal (GI) death
What is the breakage of the backbone (thread of macromolecule)?
Main-chain scission
Radiation 1m from the patient is 0.1% of the intensity of the useful beam at the patient is describing what?
scatter
What should never go over 1mGya/hr at a distance of one meter from the housing?
leakage
What death occurs within 4-10 days of exposure caused by the severe damage to the cells living in the intestines?
gastrointestinal (GI) death
What radiation effect on a macromolecule reduces in size?
main-chain scission
What is the minimum source to image receptor distance that can be used on mobile units?
no less than 30cm
What is damage and death due to fluid build up on the brain?
central nervous system (CNS) death
What radiation effect on a macromolecule has a reduction of viscosity?
Main-chain scission
What is the minimum source to image receptor distance that can be used on fluoroscopy/stationary units?
no less than 38cm
Symptoms including nausea, vomiting, loss of vision, seizures and loss of equilibrium correlate to what syndrome?
Central Nervous System Death
What radiation effect on a macromolecule has small spur-like structures?
Cross-linking
High-risk areas for radiologic technologists include:
fluoro & mobiles
What attaches to a neighboring macromolecule or to another segment of the same molecule?
Cross-linking
Define Radiodermatitis
non-malignant change in skin due to chronic exposure to radiation
What is the main cause of radiodermatitis?
no protection in fluoro.
What radiation effect on a macromolecule increases the viscosity of the solution?
Cross-linking
Exposure time adjusted for constant mAs should have constant output radiation intensity is defining what?
linearity
what is the relative risk formula?
observed / expected = Relative
What is the maximum linearity variation?
0.1
Sometimes macromolecule have these, and sometimes they are caused by radiation....
Cross-linking
What does PBL stand for?
Positive Beam Limitation
What is the excess risk formula?
Observed - Expected = Excess
What is the disruption of single chemical bonds (bond breaks due to the free radicals)?
Point lesions
Automatic light localized variable aperture collimators are available on most new equipment in the U.S. is defining what?
PBL (Positive Beam Limitation)
If you knew several dose levels, what model would you use to estimate risk for late effects?
Absolute Risk Estimates
What results in a minor modification of the molecule which can cause it to malfunction in the cell?
Point lesions
PBL must be accurate to ________ of the SID.
0.02
Name two medical conditions that have been treated with therapeutic radiation exposure in the past.
Ankolysing Spondolytis and enlarged Thymus glands in children
What term is known as, at a low dose, thought to be the cellular radiation damage that results in stochastic radiation effects observed at the whole body level?
Point lesions
What radiation effects on a macromolecule is non-detectable and has no effect?
Point lesions
Patients with ankolysing spondylitis developed what when treated with radiation?
Leukemia
Other than a high-dose fluoroscopy situation like IR procedures, the intensity of the x-ray beam at the table top of an image intensified fluoroscopic unit does not exceed ______________.
21 mGya/min
What is the efficiency of a 0.1 mm Pb equivalent apron at 75 kVp?
99
Children with enlarged thymus glands were treated with radiation and developed what due to this?
Cancer
What radiation effect on macromolecules doesn't have a change in viscosity?
Point lesions
What dosimeter is more sensitive?
OSL
What is the most difficult chromosomal aberration to detect?
Reciprocal Traanslocations
When talking about macromolecular synthesis.. What is the process of constructing the messenger RNA?
Transcription
What dosimeter is based on optically stimulated luminescence concept (laser light)?
OSL
When talking about macromolecular synthesis.. What is the addition of the amino acid?
Transfer
When is it most appropriate to perform epidemiological studies?
when a large amount of people are exposed and the number of people affected is small
What dosimeter uses aluminum oxide for the radiation material?
OSL
what is an orderly map of all chromosomes?
Karotype
When talking about macromolecular synthesis.. What forms the protein molecule from messenger RNA?
Translation
What dosimeter can be reanalyzed?
OSL
Describe a karyotype.
A Cut and paste of similar chromosomes aligning them according to length.
What macromolecule is most radiosensitive?
Protein
The severity of response is dose related" means what?
Threshold, or a certain dose must be met for a response to occur or dose raises, response raises
What is more abundant than nuclear acids (DNA & RNA)?
Protein
What dosimeter gives different qualitative measures?
OSL
describe the results of the oxford study.
there is an overall risk for leukemia of approx. 1.5 from diagnostic irradiation in utero.
The genetic code of DNA is _______________ by mRNA and _____________ to tRNA , which _______________ it into a protein.
transcribed ; transferred ; translated
What is a cutie pie?
an ionization chamber that is portable
What is a survey instrument that is used for radiation surveys when exposure levels are an excess of 10uGya/hr?
ionization chamber (cutie pie)
What is relative risk used for?
large populations with no knowledge of a dose
What is the most important molecule in the human body?
DNA
What is the most common ionization chamber?
cutie pie
If the relative risk is less than 1 it means what?
no risk
What ultimately controls cell and human growth and development?
DNA
What does GSD stand for?
Genetically Significant Dose
The most radiosensitive phase in a developing male gamete is?
Spermatogonia
What disease targets DNA?
malignant disease
What is the importance for GSD?
possible genetic responses and estimates genetic risk at the population gene pool levels
The most radiosensitive phase in a developing female gamete is?
The Mature Folicle
What molecule is important when talking about, in-vivo radiation?
DNA
What is the key role of lymphocytes?
Immune response
visible chromosome aberrations occur when...
there is damage to the DNA is sever
What is GSD?
estimated gonadal dose received by the population
Does GSD include background radiation?
background radiation is a baseline so any above exposure is significant
What are the early effects of radiation exposure?
Deterministic, Quick and High
What is another name for chromosome abberation?
cytogenetic damage
What is the specific GSD for the U.S.?
0.2 mGyt/per year
What are the late effects of radiation exposure?
Stochastic, these are late in life or even in subsequent generations and are often hard to prove as a response of exposure.
DNA can be damaged without, what?
production of a visible chromosome aberration
What is the GSD for the U.S. if there background radiation is added?
1.2 mGyt/per year
What is the most devastating human response to radiation exposure?
death
What are the effects on DNA?
cells death, malignant disease, & genetic damage
Scintillation detectors are used in what modality/modalities?
-nuclear medicine ; gamma camera
- detector arrays of many CT scanners
-image receptors for digital imaging systems
True/False: Diagnostic xray beams are intense and large enough to cause death
FALSE
What kind of radiation effect, effects DNA and causes cell death?
Deterministic effect
What means giving off a spark or flash of light?
scintillate
A dose of 15Gyt and is known as a ulceration of the skin?
desquamation
What kind of radation effect, effects DNA and causes malignant disease?
Stochastic effect
What allows from cell recovery?
fractionation
Regarding modality devices, scintillators use what crystals?
inorganic crystals
When damage to the DNA can result in abnormal metabolic activity is known as what?
malignant disease
What is rapid proliferation of cells, in an uncontrolled manner?
Malignant disease
What do the scintillator crystals consist of?
Thallium-activated sodium iodine & Thallium-activited cesium iodine
Define epilation?
hair loss
What is thallium-activated sodium iodine located in?
nuclear medicine devices & CT scanner detector arrays
What is the dose required for temporary epilation?
3Gyt
If DNA damage is to a germ cell, it is known as what?
genetic damage
What is thallium-activated cesium iodine located in?
newer generation image intensifier tubes as in the input phosphors & CT scanner detector arrays
What is the dose required for permanent epilation?
7Gyt
What kind of damage to the DNA will not be observed until the following generation or even later?
genetic damage
After exposure to ionizing radiation, heating allows for the measurement of the intensity of the emitted light via the glow curve for what device?
TLD (Thermoluminescence Dosimetry)
What is the likely timeframe if a single dose in excess of 5000 rads from total body irradiation causes death primarily due to the CNS syndrome?
within 3 days
What DNA radiation damage effect a has the most greatest concern?
genetic damage
TLDs use what type of crystal?
Lithium Fluoride (LiF)
What minimum ovarian dose caused temporary sterility?
2Gyt
What are the 5 types of damages that occur in DNA?
1. one side rail severed
2. both side rails severed
3. cross-linking
4. rung breakage
5. point lesion
A common type of gas-filled radiation detector use to detect contamination is the:
Geiger-Muller detector
What minimum ovarian dose caused permanent sterility?
5Gyt
What is the separation of bases in DNA damage?
rung breakage
What does ESE stand for?
Entrance Skin Exposure
What is molecular lesion of the DNA (genetic mutation)?
Point lesions
What is the dose of radiation expected to cause death within 60 days to 50% of those exposed to 3.5Gyt?
LD 50/60
What is the easiest way to calculate skin exposure?
ESE
A change or loss of a base that destroys the triplet code?
Point lesions
What minimum testicular dose causes transient sterility?
2Gyt
what is the average radiation dose to the entire active bone marrow that is estimated from ESE?
bone marrow dose
What is the dose required to cause patient death?
lethal dose
What is known when a creation of an abnormal gene that may not be reversed?
Point lesions
What do you use if you don't have ESE?
nomogram
What can be passed down to daughter cells?
Point lesions
What minimum testicular dose causes permanent sterility?
5Gyt
The output radiation intensity should be constant from one exposure to another is defining what?
reproducibility
What is the dose of ionizing radiation required to affect 50% of persons irradiated using 5Gyt?
SED50
What does "Radio-" mean?
due to radiation
The average variation in radiation intensity during repeated exposures should not exceed ____________.
0.05
What does SED stand for?
skin erythema dose
What does "-lysis" mean?
breaking down/dissociation
Lithium fluoride provides a nearly ___________ equivalent dosimeter.
tissue
What is an atom with too many or too few electrons?
ion
What is the same dose delivered in equal portions at regular intervals known as?
fractionation
A dose of 5Gyt, and is sunburn-like redding?
erythema
What is an electrically charged particle?
ion
What caused film badges to fog when left in your car?
temperature and/or humidity
What are the pros for film badges in regards to cost and accuracy?
inexpensive, fairly accurate, easy to process
A dose of 7Gyt and is known as permanent hair loss?
permanent epilation
What is uncharged molecules with a single unpaired electron in the valance shell (outer shell)?
Free radicals
What are the cons for film badges in regards to cost and accuracy?
cannot be reused/must be changed once a month, cannot measure less than 100uGya (10mR)
What is the physical process of converting an atom or molecule into an ion by changing the number of protons or electrons?
ionization
A dose of 3Gyt and is also known as temporary hair loss?
temporary epilation
What must dosimetry reports include?
current exposure period, annual exposure, and lifetime exposure
What tissues are first affected by radiation?
skin, gonads, and bone marrow
When water is irradiated, it dissociates into other molecular products:
ions & free radicals
What is the number one reason for retakes?
tech related error
The cells of what layer of the skin are the most sensitive?
Epidermis (Basal Cells)
When water is irradiated it dissociated into what?
a ion pair
Why is the epidermis the most sensitive when irradiated?
because thats where basal cells are located and as those cells mature they migrate to the surface
HOH+ and HOH- may dissociate into what?
smaller molecules
A beam passes through a barrier of a TVL of 1. The same intensity of beam passes through a barrier of 1 HVL. Which beam is most reduced?
TVL
1 TVL = how many HVL?
3.3
What are the 2 most radiosensitive cells in the body?
lymphocytes and spermatogonia
HOH+ ----> ?
H+ and OH*
Is the occupation of a radiographer considered the be safe?
yes, our risk of death is the same as other safe industries
Why was lung cancer most common with miners with working around uranium and radium?
because the uranium would decay into radon which is an alpha emitter; then when inhaled caused lung cancer
HOH- ----> ?
OH- and H*
What is the full term exposure limits during pregnancy?
5mSv (500rem)
What form of cancer was most common when miners were around uranium and radium?
lung cancer
What happens when ions form H+ and OH-?
form water (H2O)
What are the monthly exposure limits during pregnancy?
0.5mSv (50rem)
What is the average time between exposure and death (whole body)?
mean survival time (MST)
Free radicals can form what?
Point lesions
True/False: Skin and extremities both have a DL of 500mSv/yr (50rem).
TRUE
What does it mean when the manifestation of acute radiation sickness occurs after the 2 periods?
After latent, syndrome reveals itself (manifest illness)
What can cause biological damage?
Free radicals
Lens of the eye dose limit:
150mSv (15rem/yr)
What death is associated with doses in excess of 50Gyt (5,000rad)?
central nervous system (CNS) death
What is an uncharged molecule with a single unpaired electron in the outermost shell?
Free radicals
What syndrome always results in death, max life is 3 days?
central nervous system (CNS) death
What is chemically unstable?
Free radicals
The general population exposure if ___________mrem/yr while a radiographer's annual dose limit _________mrem/yr.
100; 1mSv/yr
5,000; 50mSv/yr
What were the conclusions of Muelller's experiments?
Radiation dose dose not alter quality of mutations, but increases the frequency of mutations observed.
What trimester is associated with possible childhood malignancies?
2nd-3rd trimester
What is highly reactive?
Free radicals
What first couple weeks of pregnancy has a possibility of congential abnormalities?
week 2-10
H. J. Mueller experimented on what?
Fruit Flies
What can produce toxins?
Free radicals
When does resorption occur?
first 2 weeks of pregnancy
Why is Thorotrast no longer used in radiography?
Causes Liver Cancer
What has a lifetime of less than 1 ms?
Free radicals
Natural occurrence of live births resulting in a congenital abnormality is 5%. What percent increase would you expect to see a 100mGy fetal dose?
1% increase
What did Russell experiment on?
8,000,000 + mice
In a lifetime of less than 1 ms when talking about free radicals, what can happen?
able to defuse of flow through the cell and interact at a distant site
OH* joins with a similar molecule to form what?
hydrogen peroxide
What were the 3 conclusions of Russels experiments?
Dose rate effect does exist, dose determines severity, and development of dose doubling concept.
A pregnant patient is irradiated-what should be done first & what are some other considerations?
-estimate the fetal dose-done by a physicist
-determine the stage of gestation
-use the 100 to 25mGy rule
-make detailed notes in patient's chart
The commonly accepted estimate for radiation induced life-span shortening is _____ days/rad.
1 day/10 miliGy
OH
+ OH
= ?
H2O2
What is the maximum lifetime cumulative exposure for a technologist 41 years old?
410mSv
Protective aprons must have a Pb equivalent of ______________ and _____________ Pb equivalent is recommended.
0.25mm ; 0.5mm
The worst case estimate for radiation induced life-span shortening in days/rad is _____.
10 days/10 miliGy
Hydrogen peroxide formation is what?
toxic to the cell
Regarding DRT (digital radiographic tomosynthesis), what advantages does it appear to have over CT?
reduces patient dose
What are the effects of an irradiated fetus at 2-12 weeks?
congenital abnormalities
H* can interact with oxygen to form what?
hydroperoxyl radical
What is the average ESD for a fluoroscopic examination?
40mGyt/min
What are the effects of an irradiated fetus 0-2 weeks?
prenatal death or no effects
For diagnostic x-ray personnel, the highest occupational exposure occurs during _______________ exams.
fluoroscopy & mobile radiography
What syndromes are involved in the acute radiation sickness?
#NAME?
What if two hydroperoxyl radicals combine?
can be toxic to the cell
What is the most common mistake associated with the latent period?
it is sometimes mistaken as early recovery from a moderate radiation dose
The interaction of two hydroperoxyl radicals form what?
hydrogen peroxide
Personnel working in interventional radiography should be provided with _____________.
extremity monitoring
A subject, still alive on day 2 after a catastrophic event, would not experience _______ following a dose high enough to cause CNS syndrome.
Hematologic and Gastrointestinal Syndromes
What are the main damaging products resulting from radiolysis of water?
hydrogen peroxide & hydroperoxyl
The lens of the eye should never receive more than ________ per year.
150 mSv (15rem)
For nursing personnel present during mobile x-ray imaging, a personnel monitoring device is required __________.
not at all
The destruction of _______ cells in the intestinal lining causes death from GI syndrome.
Stem
When radiation reacts with biologic material two thing can occur:
direct effect & indirect effect
The dose limit to the extremities is _________.
500 mSv/yr (50 rem/yr)
The bi-numeral range of the LD 50/50 for humans is approximately.
3-4 Gy
If the initial ionizing event occurs on that molecule , the effect is said to be direct (it strikes a target, such as a DNA molecule) is is known as what?
Direct effect
The dose limit to the general public is ____________.
1 mSv/yr (100mrem/yr)
Some radiation victims of _______ syndrome may recover completely.
Hematologic
Direct action is more likely to occur due to what ?
high LET
True/False: Technologists working fluoroscopy should use the radiologist as shielding whenever possible in addition to the apron and curtain.
TRUE
The Latent period would be brief or non-existent when the dose is ____.
significantly high
When the initial ionizing event occurs on a distant, non-critical molecule that transfers the energy of ionization to the target molecule is known as what?
indirect effect
A patient accidentally subjected to a dose equivalent of 30 Gy would probably die as a result of which type of acute radiation syndrome?
Gastrointestinal Death
Is the effect of radiation on human DNA, direct or indirect?
indirect, because 80% of water in body
Every radiology department should provide a radiation safety program that includes:
#NAME?
True/False: Maximum Permissible Dose (MPD), a current used radiologic concept for occupational dose, is a dose that would be expected to produce a significant radiation effect.
FALSE
Radiation protection guidelines for radiographers are based on what?
Stochastic effects
What is the measure of radiosensitivity of the cell?
D37
Optically stimulated luminescence (OSL) monitors are superior to the thermoluminescent dosimeters in that they are ____________.
more sensitive to low exposure
Relative = _____ / ______?
observed cases / expected cases
If you have a "low" D37, you are considered to be?
highly radiosensitive
Patient dose is usually estimated by conducting simulated x-ray examinations with __________.
human phantoms and test objects
A study of an irradiated population which showed a relative risk factor below 1.0 would indicate that the population had a _____ risk?
reduced
If you have a "high" D37, you are considered to be?
radioresistant
True/False: The frequency of x-ray examination being performed is increasing in all age groups.
TRUE
The United States should be concerned about _______ in Russia and around the world.
Nuclear Power Plants
If oxygen is present the indirect effect is what?
amplified
What was the main cause of partial meltdown at 3 mile island?
Human Error
Patient skin exposure can be measured indirectly by using a _____.
nomogram
For cell death to happen, the target molecule must be ?
inactivated
In target theory, a hit may be cause by what kind of interaction?
direct or indirect
It is difficult to link cancer to radiation exposure because cancer occurs in __________.
General populations
Acute skin effects from radiation exposure have been reported following _________ exams.
angiointerventional
Bone marrow dose is measured _________.
as an estimate from ESE
Regarding the the radiosensitivity of macromolecules, the most radiosensitive is:
DNA
Out of the 4 types of mature blood cells, which one is the most radiosensitive?
lymphocytes
Most cellular radiation damage resulting in a late total body effect and thought to be the site of radiation induced malignancies, is known as:
Point lesions
What only effect is observed in late and early effects?
chromosome abberations
The simplest way to measure patient dose is to measure the ________.
entrance skin exposure (ESE)
What is a map of chromosomes?
karyotype
What does in vivo refer to?
inside of the cell
The radiation dose monitor most frequently used to measure patient exposure is the ________.
TLD (thermoluminescent dosimeter)
The generically significant dose for the general public is important because of the risk of __________.
effects if the gene pool
What are the 4 types of aberrations?
#NAME?
What does in vitro refer to?
outside of the cell
True/False: Digital mammography results in lower doses than screen/film mammography.
TRUE
What % of people will develop a malignant disease?
0.33
Is in vivo radiosensitive or radioresistant?
radiosensitive
What does SED stand for?
Skin Erythmia Dose
At what exposed dose should someone abstain from procreation?
100 miliGy
A decrease in lymphocytes count indicates what?
disease and/or radiation exposure
What arthritis-like condition of the vertebral column was being cured by radiation, which later resulted in luekemia?
ankylosing spondylitis
What type of cancers are radiation-induced?
thyroid, bone, skin, breast, lung, liver
What types of cancers are NOT radiation-induced?
colon, brain, testicular, cervix, ovarian
What effect would low dose chronic radiation have on fertility?
no effect
What is the weakest area of knowledge concerning radiobiology?
genetic effects
In relative risk, pertaining to the Oxford study, 1.5 from diagnostic increases the chance of disease by how much %?
0.5
A karyotype displays how many chromosome pairs?
23 pairs
Patients with TB were treated with fluor to induce a pneumothorax and developed _____?
Breast Cancer
Patients treated with radium salts developed _____?
bone cancer
Linear Non Threshold was discovered by whom?
H. J. Mueller
What is doubling Dose?
The dose of radiation that produces twice the frequency of genetic mutations as would have been observed without the radiation
H. J. Mueller's research caused what to be lowered?
the permissible dose limit
Patients treated with thorotrast developed _____?
Liver cancer
Patients with ringworm treated with radiation developed _____?
permanent epilation
What are the two principle late effects of radiation exposure?
genetic effects & malignancy
True/False: CT is considered a low-dose procedure for the patient.
FALSE
What can be seen WITHOUT a karyotype?
single-hit chromosome aberration
Is in vitro radiosensitive or radioresistant?
radioresistant
What is deviation from normal (abnormal) ?
abberation
The period of major organogenesis is during the ________ of pregnancy.
second to tenth week
What can be seen WITH a karyotype?
reciprocal translocation
Patient dose can be reduced by using _________.
higher kVp
What can be ONLY be seen WITH a karyotype?
multi-hit chromosome aberration
What is relating to or caused by poison?
toxic
Health physics is concerned with minimizing radiation dose to ______.
#NAME?
What % of people will die of cancer?
0.2
What usually has late effects and has low exposures, takes months and years later, and any dose can produce a response?
Stochastic
What usually has early effects and high exposures , takes minutes or days later, and can vary with dose?
Deterministic
Exposure is measured by multiplying _____ by _____.
exposure rate, exposure time
What is the term used to describe calloused, weathered skin?
Radiodermatitis
In 2005, how many years earlier did radiologists die versus the general population?
0 Years
True/False: Macromolecular synthesis of proteins, RNA and DNA is critical to the survival of the cell and to its replication?
TRUE
Dose limits are based on a ________ dose-response relationship to radiation.
linear, nonthreshold
The concept of effective dose accounts for the ____________.
different types of radiation & relative radiosensitivity of various tissues and organs
Who was at risk for developing radiation induced cataracts?
Physicists
The breakage of the thread or backbone is a long-chain macromolecule when irradiated in vitro is called:
main-chain scission
The collimator light must be accurate to with in ________% of the SID.
2
What are the 4 types of mature blood cells?
#NAME?
What are the three principal observable effects resulting from irradiation of DNA in vivo?
cell death, malignant disease, and genetic death
Regarding viscosity, after cross-linking occurs, describe the irradiated in vitro solution:
increases the viscosity of the solution
Positive beam limitation(PBL) must be accurate to within _________% of the SID.
2
If the dose is increased what happens to the prodromal and latent periods?
They decrease.
What is the minimum requirement for filtration on x-ray equipment operating above 70 kVp?
2.5 mm Al equivalent
If the dose of radiation is increased what does that mean for the severity and response of the disease?
increased
What is a free radical?
uncharges molecules with a single unpaired electron in the valance, highly reactive & chemically unstable, can produce toxins, has life time of less 1 ms, and can cause biological damage
The output intensities of reproduced exposures should not be vary more than ________% from each other.
5
Pertaining to acute radiation sickness, when the symptoms present themselves this is known as what?
Manifest Illness
When HOH+ and HOH- dissociates into smaller molecules, what does the HOH+ separate into?
H+ and OH*
Measuring the relationship between the output intensities of adjacent mA stations is a test of _________.
linearity
When HOH+ and HOH- dissociates into smaller molecules, the HOH- separates into:
OH- and H*
The source-to-skin distance must be no less than __________cm on stationary fluoroscopes.
38
The _________ phase of ___________________ is said to resemble a zipper opening.
S ; DNA synthesis
The free radicals produced during of water are:
H
and OH
primary radiation is _________.
the useful beam
A quantity that reflects both dose and volume of tissue irradiated is the _______.
dose area product
2 hydroperoxly free radicals joined form what? and chemical expression.
Hydrogen peroxide ; H2O2 +O2
Half-Value layer (HVL) is related to what principles of radiation protection?
shielding
An initial ionizing event occurs on a distant, non-critical molecule that transfers the energy of ionization to a target molecule. Is this effect direct or indirect.
indirect
True/False: When oxygen is present, the kill ratio of cells is decreased.
False, it increases in kill ratio of cells
If all other factors remain constant, radiation dose is related to x-ray beam-on time:
directly
This radiation effect on a macromolecule has a sticky substance on the end that attaches to neighbors or to another segment of the same molecule. What effect is this?
cross-linking
If all other factors remain constant, radiation dose is related tp source-to-object distance (SOD):
by the inverse square
What is mitosis, when discussing radiosensitivity?
most sensitive
One tenth-value layer (TVL) is defined as:
the shielding necessary to reduce exposure to 1/10
What is late S phase, when discussing radiosensivity?
least sensitive
One TVL is equal to approximately how many HVL's?
3.3
What is G1 going on to early S phase, when discussing radiosensitivty?
2nd most sensitive
During radiography, the best position for the radiologic technologist is?
behind the operating console barrier
Regarding viscosity, when main-chain scission occurs in the solution, the irradiated in vitro solution is:
reduction/decrease in viscosity
The occupational effective dose is assumed to be:
<10% of monitored dose
An RED is?
a sealed source of radiative material that directly exposes people
The OH free radical can join with a similar molecules and form the most damaging product to the human cell and that toxic agent is: formula and name.
Hydrogen peroxide ; H2O2
Most occupational dose to radiographers occurs during which type of exam?
fluoroscopy
What is radiolysis?
the breaking down/dissociation due to radiation
Every diagnostic x-ray tube housing must be sufficiently shielding to limit the level of exposure 1m from the housing to:
1 mGya/hr
D37 is a measure of radiosensitivity that relates to 37% _______________ (survival or death?)
survival
What happens if radiation reacted uniformly?
100% of cells would hit equally and radiation would be wasted
The minimum permissible filtration for general purpose radiographic or fluoroscopic tube is:
2.5mm Al
D37 supports that radiaiton is what?
random
The fluoroscopic tube should not be positioned closer than 38cm to the tabletop because the:
patient radiation dose would be excessive
In D37, what is the surviving portion of cells and what is the dose required to kill?
37% survival and 63% to kill
Which of the following is regulated in a controlled area?
public access
Which of the following usually is considered to be a secondary protective barrier?
control booth barrier
When an atom of water is irradiated it first dissociates into _____________.
an ion pair
Fluoroscopic x-ray units must:
have at least 2.5 mm Al equivalent filtration
H* is concerning if it joins with oxygen to form _______________ molecules.
hydroperoxyl
Which of the following contributes to the exposure of radiologic personnel?
scatter radiation
A reactive atom or molecule having an unpaired electron in its outer shell is:
free radical
The design limit for exposure of occupants in controlled areas is:
1 mSv/wk
In vitro irradiation of macromolecules (non DNA) causes _________________ damage to macromolecules.
repairable & reversible
We measure ______________ instead of _______________ to determine the lethal effects of radiation.
Survival of cells, Cell death
All fluoroscopes have a 5-minute reset timer:
to protect the patient
Molecular lesions of DNA are called ____________.
point mutations
A test to ensure that radiation intensity is doubled when radiographic mA is doubled is called a test of:
linearity
When the fluoroscopic x-ray tube is mounted farther under the table, what is reduced?
patient dose
The principal radiation interacts within the human body is with _____________.
Water
Which of the following is used in thermoluminescent dosimetry?
lithium fluoride
A type of DNA damage that may not be reversible is a ______________.
base change or loss
The resolving time of a radiation detector is the time required:
to detect sequential ionization
The amount of light emitted by a scintillation phosphor is proportional to what feature of photon energy?
absorbed
In thermoluminescence dosimetry, a plot of output intensity versus temperature is called a:
glow curve
The GSD from medical radiation exposure depends on all the following except the:
occupational exposure
Which of the following units is most appropriate when patient dose is expressed?
gray
Which of the following procedures might result in an ESE that exceeds 100mGya?
5 minutes of fluoroscopy
The GSD is:
an index of radiation received by the gene pool
In the United States, the GSD from medical radiation exposure is approximately:
0.2 mGya/yr
Medical radiation dose to the total population:
has greatly increased in the past few decades
Which of the following is the most likely to produce a skin burn due to ionizing radiation?
interventional cardiology procedure
When a second radiation monitor is provided to a pregnant radiologic technologist:
it should be worn under the apron at waist level
What could a radiologic technologist due to reduce the radiation dose to the fetus of a pregnant patient?
use specific area shields if appropriate
A patient is to undergo radiologic examination because of low back pain. As she is being positioned, she asks whether this will affect her current pregnancy. What should the technologist do?
seek advice from the radiologist before proceeding
After a skull series, a brain scan, a barium enema, and an intravenous pyelogram, it is discovered that the patient is pregnant. What is the correct course of action?
estimate the fetal dose
The greatest nonlethal radiation hazard to an embryo or fetus occurs:
at 2 to 8 weeks of gestation
The National Council on Radiation Protection and Measurements (NCRPM) recommends a therapeutic abortion if the fetal dose exceeds:
no recommendation is made
In pelvis radiography, a dose to the shielding female gonads is primarily due to the:
internally scattered x-rays
When a radiologic technologist becomes pregnant, she should be:
counseled on proper radiation safety
For a pregnant radiologic technologist, required radiation protection practice includes which of the following?
providing two radiation monitors
The fetal dose below which termination of pregnancy need not be considered is approximately:
0.1 Gyt (10rad)
To protect a patient from soft radiation, one should use which of the following?
increased filtration
In the production of an acceptable radiograph, patient dose increase as ____________________ increases
the grid ratio
What is the approximate annual occupational exposure received by a radiologic technologist?
0.5 mSv (50rem)
Which of the following should not be part of a personnel radiation monitoring program?
routine blood exam
To reduce occupational exposure during mobile x-ray examination:
the radiologic technologist should wear a protective apron
In evaluation of a personnel monitoring report:
whole-body dose is usually highest
Recommendation proposed for mobile x-ray imaging systems state that the exposure cord length should be at least:
1.8m
Personnel monitoring is required:
when it is likely that one will receive 1/10 the DL
Which of the following personnel monitors can be worn the longest?
TLD device
During fluoroscopy, the personnel radiation monitor should be worn:
on the collar, outside the apron
A 0.5 mm Pb equivalent apron attenuates a 75kVp x-ray beam by approximately:
0.9
Which of the following statements about the use of protective apparel is true?
Gloves should be worn by all who hold patients during the x-ray exam
Which of the following is an advantage of film over TLD for personnel monitoring?
is cheaper
Personnel monitoring of the extremities is necessary:
during angio/interventional procedures
For radiologists, protective eyewear:
is unnecessary