Radiation Biology Questions and
Answers 100% Solved
Why should diagnostic imaging personnel be familiar with standardized radiation quantities and
units? Diagnostic imaging personnel should be familiar with standardized radiation
quantities and units so exposure to personnel and the patient is measured in a consistent and
uniform manner, and dose remains as low as possible. Dose limits and standardized radiation
quantities are established to minimize the negative effects of exposure to both the patient and
the technologist. (page 62)
When, where, and how did Wilhelm Conrad Roentgen discover x-rays? Wilhelm Conrad
Roentgen discovered x-rays on November 8, 1895 while working in a lab at the University of
Wurzburg in Bavaria. While experimenting with cathode rays and fluorescent materials, he
passed an electric charge through a partial vacuum discharge tube (Crookes tube) and observed
a light emerge from the piece of paper coated with barium platino-cyanide that was a bench
near him. He realized that there must have been some sort of radiant energy that was emitted
from the Crookes tube when the barium platino-cyanide started to glow. He experimented more
with various items that he put between the Crookes tube and the fluorescent-coated paper and
found that most of these materials would allow the new rays to pass through them, therefore
discovering the "x-ray". (page 62).
hat type of medical problems did early radiation workers develop as a consequence of their
occupational exposure? The type of medical problems early radiation workers developed
as a consequence of their occupational exposure were somatic, meaning biologic damage to the
body of the exposed individual caused by exposure to ionizing radiation. These medical
problems included radiation-induced cancer, reddening of the skin called radiodermatitis, skin
lesions that became cancerous, and blood disorders such as aplastic anemia and leukemia.
(page 63).
What is the benefit of using the International System of Units of measurement for ionizing
radiation? The International System of Units of measurement makes it possible the
interchange of units among all branches of science throughout the world. (pg. 66)
, What is a threshold dose? A threshold dose is a dose of radiation lower then which an
individual had a negligible chance of sustaining specific biologic damage. (pg. 65)
In 1991 the International Commission on Radiological Protection (ICRP) revised tissue weighting
factors. On what data was this revision based? The revision made by the International
Commission on Radiological Protection in 1991 was based on data from more recent
epidemiologic studies of the atomic bomb survivors. (pg. 67)
What radiation quantities are currently in use, and what traditional and SI units are used to
relate these quantities? The radiation quantities than are currently used are exposure (X),
absorbed dose, effective dose, collective dose and equivalent dose. The traditional and SI for
each are the following : exposure is coulomb/kg and R, absorbed dose is gray and joule per
kilogram, effective dose is Sievert and Rem, collective dose is man-men and person-Sievert and
equivalent dose is Sievert and Rem. (page 71, 73, 76, and 78)
What factors determine the amount of x-ray energy absorbed by a human anatomic structure?
Factors that determine the amount of x-ray energy absorbed by a human anatomic
structure are different atomic numbers within tissues, density of tissues and the energy of an
incident photon can change. (page 72)
When a person receives exposure from various types of ionizing radiation, what radiation
quantity and what SI and traditional unit can be used for radiation protection purposes?
When a person receives exposure from various types of ionizing radiation the quantity
used is effective does (EfD). The SI unit used for EfD is Sievert and the traditional unit is Rem.
(page 70 and 76)
What are the consequences of ionization in the human cell? Creation of unstable atoms,
production of free electrons, production of low-energy x-ray photons, creation of reactive free
radicals capable of producing substances poisonous to the cell, creation of new biologic
molecules detrimental to the living cell, injury to the cell that may manifest itself as abnormal
function or loss of function. (box 1-1 on page 2)
When is medical radiation exposure considered unnecessary? When it doesn't benefit
the patient- examples: lack of collimation, wrong exam, repeats.
Answers 100% Solved
Why should diagnostic imaging personnel be familiar with standardized radiation quantities and
units? Diagnostic imaging personnel should be familiar with standardized radiation
quantities and units so exposure to personnel and the patient is measured in a consistent and
uniform manner, and dose remains as low as possible. Dose limits and standardized radiation
quantities are established to minimize the negative effects of exposure to both the patient and
the technologist. (page 62)
When, where, and how did Wilhelm Conrad Roentgen discover x-rays? Wilhelm Conrad
Roentgen discovered x-rays on November 8, 1895 while working in a lab at the University of
Wurzburg in Bavaria. While experimenting with cathode rays and fluorescent materials, he
passed an electric charge through a partial vacuum discharge tube (Crookes tube) and observed
a light emerge from the piece of paper coated with barium platino-cyanide that was a bench
near him. He realized that there must have been some sort of radiant energy that was emitted
from the Crookes tube when the barium platino-cyanide started to glow. He experimented more
with various items that he put between the Crookes tube and the fluorescent-coated paper and
found that most of these materials would allow the new rays to pass through them, therefore
discovering the "x-ray". (page 62).
hat type of medical problems did early radiation workers develop as a consequence of their
occupational exposure? The type of medical problems early radiation workers developed
as a consequence of their occupational exposure were somatic, meaning biologic damage to the
body of the exposed individual caused by exposure to ionizing radiation. These medical
problems included radiation-induced cancer, reddening of the skin called radiodermatitis, skin
lesions that became cancerous, and blood disorders such as aplastic anemia and leukemia.
(page 63).
What is the benefit of using the International System of Units of measurement for ionizing
radiation? The International System of Units of measurement makes it possible the
interchange of units among all branches of science throughout the world. (pg. 66)
, What is a threshold dose? A threshold dose is a dose of radiation lower then which an
individual had a negligible chance of sustaining specific biologic damage. (pg. 65)
In 1991 the International Commission on Radiological Protection (ICRP) revised tissue weighting
factors. On what data was this revision based? The revision made by the International
Commission on Radiological Protection in 1991 was based on data from more recent
epidemiologic studies of the atomic bomb survivors. (pg. 67)
What radiation quantities are currently in use, and what traditional and SI units are used to
relate these quantities? The radiation quantities than are currently used are exposure (X),
absorbed dose, effective dose, collective dose and equivalent dose. The traditional and SI for
each are the following : exposure is coulomb/kg and R, absorbed dose is gray and joule per
kilogram, effective dose is Sievert and Rem, collective dose is man-men and person-Sievert and
equivalent dose is Sievert and Rem. (page 71, 73, 76, and 78)
What factors determine the amount of x-ray energy absorbed by a human anatomic structure?
Factors that determine the amount of x-ray energy absorbed by a human anatomic
structure are different atomic numbers within tissues, density of tissues and the energy of an
incident photon can change. (page 72)
When a person receives exposure from various types of ionizing radiation, what radiation
quantity and what SI and traditional unit can be used for radiation protection purposes?
When a person receives exposure from various types of ionizing radiation the quantity
used is effective does (EfD). The SI unit used for EfD is Sievert and the traditional unit is Rem.
(page 70 and 76)
What are the consequences of ionization in the human cell? Creation of unstable atoms,
production of free electrons, production of low-energy x-ray photons, creation of reactive free
radicals capable of producing substances poisonous to the cell, creation of new biologic
molecules detrimental to the living cell, injury to the cell that may manifest itself as abnormal
function or loss of function. (box 1-1 on page 2)
When is medical radiation exposure considered unnecessary? When it doesn't benefit
the patient- examples: lack of collimation, wrong exam, repeats.
