KETTERING COMPREHENSIVE EXAM UPDATED
QUESTIONS AND SOLUTIONS RATED A+
✔✔Dose Equivalent (rem) - ✔✔Radiation Equivalent Man
Unit of absorbed dose equivalent
SI unit equivalent to Sievert (1 Sv=100 rem)
Measurement of the biological effectiveness of radiation (the ability of radiation to
produce some predetermined biological response)
rem->Sv (x0.01)
✔✔What is the quality factor (weighting factor)? - ✔✔The absorbed dose equivalent is
equal to the absorbed dose (rad) multiplied by a quality factor
QF's are units of comparison between x-rays and other forms of ionizing radiation
Gy X QF= Sv
✔✔QF for X-rays - ✔✔1
✔✔QF for Gamma rays - ✔✔1
✔✔QF for Beta particles - ✔✔1
✔✔QF for Fast Neutrons - ✔✔10
✔✔QF for protons - ✔✔2-5
✔✔QF for alpha particles - ✔✔20
✔✔Exposure (roentgen) - ✔✔Defines the unit of radiation exposure that will yield 2.58 x
10^-4 coulombs per kilogram of air (C/kg/Air Kerma/mGy(t)(a)
✔✔Curie (Ci) - ✔✔unit of radioactivity
SI unit Becquerel (Bq)
✔✔Non-Threshold dose effect relationship - ✔✔"NOT-SAFE"
No amount of radiation, regardless of dose, is safe
Always starts in the corner of graphs
✔✔Threshold dose effect relationship - ✔✔Some amount of radiation is required before
a measurable effect can be detected
Dont start in the corners
✔✔Linear - ✔✔constant slope
-observed response is directly proportional to the dose
-a radiation dose that is doubled would double the response
, ✔✔Non-linear (curvilinear) - ✔✔at some point the slope of the dose response curve
varies
-Non-linear means that an observed response is not directly proportional to the dose
-A radiation dose that is doubled would not double the response
✔✔Sigmoidal - ✔✔(S shaped) constantly varying shope of the dose response curve
✔✔Line starts in corner - ✔✔Non-Threshold
✔✔Line starts from the right side - ✔✔Threshold
✔✔Line is straight - ✔✔Linear
✔✔Line curves anywhere - ✔✔Non-linear
✔✔Law of Bergonie and Tribondeau - ✔✔cells are most sensitive to radiation when
they are immature, undifferentiated, and rapidly dividing
-Mitotic activity (cell division) radio-sensitivity increases with increased mitotic activity
-Maturity (more immature more sensitive) radio-sensitivity decreases with increased
maturity; stem cells (less mature) are more radio-sensitive than nerve cells
-Degree of specificity (muscle/nerve [more resistant]) radio-sensitivity decreases with
increased specificity (specialization); stem cells (less specificity) are more radio-
sensitive than nerve cells
✔✔Which cell is the most sensitive? - ✔✔lymphocyte
✔✔Which ones are the least to greatest sensitivity?
Stem cell/intestinal cell
Nerve
Muscle
Lymphocyte - ✔✔Nerve
Muscle
Stem/intestinal cell
Lymphocyte
✔✔Linear Energy Transfer (LET) - ✔✔Defines the rate of energy deposited per unit
track length through an absorber
Amount of radiation that is transferred to the body as the x-ray beam travels through the
body
As LET increases, the quality factor for a given form of radiation will increase
✔✔Oxygen Effect - ✔✔Defines the ability of aerobic conditions to enhance the
effectiveness of radiation
Increasing the oxygen of a cell increases the cells sensitivity to radiation
QUESTIONS AND SOLUTIONS RATED A+
✔✔Dose Equivalent (rem) - ✔✔Radiation Equivalent Man
Unit of absorbed dose equivalent
SI unit equivalent to Sievert (1 Sv=100 rem)
Measurement of the biological effectiveness of radiation (the ability of radiation to
produce some predetermined biological response)
rem->Sv (x0.01)
✔✔What is the quality factor (weighting factor)? - ✔✔The absorbed dose equivalent is
equal to the absorbed dose (rad) multiplied by a quality factor
QF's are units of comparison between x-rays and other forms of ionizing radiation
Gy X QF= Sv
✔✔QF for X-rays - ✔✔1
✔✔QF for Gamma rays - ✔✔1
✔✔QF for Beta particles - ✔✔1
✔✔QF for Fast Neutrons - ✔✔10
✔✔QF for protons - ✔✔2-5
✔✔QF for alpha particles - ✔✔20
✔✔Exposure (roentgen) - ✔✔Defines the unit of radiation exposure that will yield 2.58 x
10^-4 coulombs per kilogram of air (C/kg/Air Kerma/mGy(t)(a)
✔✔Curie (Ci) - ✔✔unit of radioactivity
SI unit Becquerel (Bq)
✔✔Non-Threshold dose effect relationship - ✔✔"NOT-SAFE"
No amount of radiation, regardless of dose, is safe
Always starts in the corner of graphs
✔✔Threshold dose effect relationship - ✔✔Some amount of radiation is required before
a measurable effect can be detected
Dont start in the corners
✔✔Linear - ✔✔constant slope
-observed response is directly proportional to the dose
-a radiation dose that is doubled would double the response
, ✔✔Non-linear (curvilinear) - ✔✔at some point the slope of the dose response curve
varies
-Non-linear means that an observed response is not directly proportional to the dose
-A radiation dose that is doubled would not double the response
✔✔Sigmoidal - ✔✔(S shaped) constantly varying shope of the dose response curve
✔✔Line starts in corner - ✔✔Non-Threshold
✔✔Line starts from the right side - ✔✔Threshold
✔✔Line is straight - ✔✔Linear
✔✔Line curves anywhere - ✔✔Non-linear
✔✔Law of Bergonie and Tribondeau - ✔✔cells are most sensitive to radiation when
they are immature, undifferentiated, and rapidly dividing
-Mitotic activity (cell division) radio-sensitivity increases with increased mitotic activity
-Maturity (more immature more sensitive) radio-sensitivity decreases with increased
maturity; stem cells (less mature) are more radio-sensitive than nerve cells
-Degree of specificity (muscle/nerve [more resistant]) radio-sensitivity decreases with
increased specificity (specialization); stem cells (less specificity) are more radio-
sensitive than nerve cells
✔✔Which cell is the most sensitive? - ✔✔lymphocyte
✔✔Which ones are the least to greatest sensitivity?
Stem cell/intestinal cell
Nerve
Muscle
Lymphocyte - ✔✔Nerve
Muscle
Stem/intestinal cell
Lymphocyte
✔✔Linear Energy Transfer (LET) - ✔✔Defines the rate of energy deposited per unit
track length through an absorber
Amount of radiation that is transferred to the body as the x-ray beam travels through the
body
As LET increases, the quality factor for a given form of radiation will increase
✔✔Oxygen Effect - ✔✔Defines the ability of aerobic conditions to enhance the
effectiveness of radiation
Increasing the oxygen of a cell increases the cells sensitivity to radiation
