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Chapter 7- Molecular and Cellular Radiation
Biology Exam Questions With Correct Answers
100% Verified.
Direct Action - Answer✔Biologic damage that occurs as a result of ionization of atoms on
essential molecules produced by straight interaction with the incident radiation
LET - Answer✔The average energy deposited per unit length of track
Covalent cross-links - Answer✔Chemical unions created between atoms by the single sharing of
one or more pairs of electrons
Radiation Weighting Factor (Wg) - Answer✔Used to calculate the equivalent dose to determine
the ability of a dose of and kind of ionizing radiation to cause biologic damage
Mutation - Answer✔Loss or change of a nitrogenous base in the DNA chain
Cell survival curve - Answer✔Classic method of displaying the sensitivity of a particular type of
cell to radiation
Indirect action - Answer✔A multistage process that first involves the production of reactive free
radicals that are created by the interaction of radiation with water molecules
OER - Answer✔The ratio of the radiation dose required to cause a particular biologic response
of cells or organism in an oxygen-deprived environment to the radiation dose required to cause
an identical response under normal oxygenated conditons
Apotosis - Answer✔Programmed cell death
Chromosome aberrations - Answer✔Results when irradiation occurs early in interphase, before
DNA synthesis takes place
Target Theory - Answer✔Concept that the cell dies if the master, or key, molecule becomes
inactivated as a consequence of exposure to ionizing radiation
1
, ©THESTAR 2024/2025 ALL RIGHTS RESERVED 11:09PM. A+
RBE - Answer✔Describes the relative capabilities of radiation with differing LET's to produce a
particular biologic reaction
Chromatid abberations - Answer✔Results from irradiation of individual chromatids occurs later
in interphase, after DNA synthesis has taken place
Law of Bergonie and Tribondeau - Answer✔The radiosensitivity of cells is directly proportional
to their reproductive activity and inversely proportional to their degree of differentiation.
Free radicals - Answer✔Solitary atoms or most often a combination of atoms that behave as
single entities and are very chemically reactive as a result of presence of unpaired valence
electrons
Mitotic delay - Answer✔Exposing a cell to as little as 0.01 Gy (1 rad) of ionizing radiation just
before it begins dividing can result in failure of the cell to start dividing on time
Chromosome breakage - Answer✔The breaking of one or both of the sugar-phosphate chains of
a DNA molecule, which can be caused by exposure of the molecule to ionizing radiation
R* - Answer✔An organic neutral free radical
Molecular damage - Answer✔Injury on the molecular level resulting from exposure to ionizing
radiation
HO2* - Answer✔hydroperoxyl radical
Germ cells - Answer✔Female and male reproductive cells
Radiation Biology - Answer✔branch of biology concerned with the effects of ionizing radiation
on living systems
Hydrogen Peroxide - Answer✔OH* + OH* = H2O2, a substance that is poisonous to the cell
Point Mutation - Answer✔Can result when ionizing radiation interacts with a DNA
macromolecule and the energy transferred in the process ruptures one of its chemical bonds
and serves one of the sugar phosphate chain side rails, or strands, of the ladderlike molecular
structure
H* and OH* - Answer✔A hydrogen radical and a hydroxyl radical
Radiation damage is observed on which of the following three levels?
A. Molecular, cellular, and inorganic systems
B. Molecular, cellular and organic systems
2
Chapter 7- Molecular and Cellular Radiation
Biology Exam Questions With Correct Answers
100% Verified.
Direct Action - Answer✔Biologic damage that occurs as a result of ionization of atoms on
essential molecules produced by straight interaction with the incident radiation
LET - Answer✔The average energy deposited per unit length of track
Covalent cross-links - Answer✔Chemical unions created between atoms by the single sharing of
one or more pairs of electrons
Radiation Weighting Factor (Wg) - Answer✔Used to calculate the equivalent dose to determine
the ability of a dose of and kind of ionizing radiation to cause biologic damage
Mutation - Answer✔Loss or change of a nitrogenous base in the DNA chain
Cell survival curve - Answer✔Classic method of displaying the sensitivity of a particular type of
cell to radiation
Indirect action - Answer✔A multistage process that first involves the production of reactive free
radicals that are created by the interaction of radiation with water molecules
OER - Answer✔The ratio of the radiation dose required to cause a particular biologic response
of cells or organism in an oxygen-deprived environment to the radiation dose required to cause
an identical response under normal oxygenated conditons
Apotosis - Answer✔Programmed cell death
Chromosome aberrations - Answer✔Results when irradiation occurs early in interphase, before
DNA synthesis takes place
Target Theory - Answer✔Concept that the cell dies if the master, or key, molecule becomes
inactivated as a consequence of exposure to ionizing radiation
1
, ©THESTAR 2024/2025 ALL RIGHTS RESERVED 11:09PM. A+
RBE - Answer✔Describes the relative capabilities of radiation with differing LET's to produce a
particular biologic reaction
Chromatid abberations - Answer✔Results from irradiation of individual chromatids occurs later
in interphase, after DNA synthesis has taken place
Law of Bergonie and Tribondeau - Answer✔The radiosensitivity of cells is directly proportional
to their reproductive activity and inversely proportional to their degree of differentiation.
Free radicals - Answer✔Solitary atoms or most often a combination of atoms that behave as
single entities and are very chemically reactive as a result of presence of unpaired valence
electrons
Mitotic delay - Answer✔Exposing a cell to as little as 0.01 Gy (1 rad) of ionizing radiation just
before it begins dividing can result in failure of the cell to start dividing on time
Chromosome breakage - Answer✔The breaking of one or both of the sugar-phosphate chains of
a DNA molecule, which can be caused by exposure of the molecule to ionizing radiation
R* - Answer✔An organic neutral free radical
Molecular damage - Answer✔Injury on the molecular level resulting from exposure to ionizing
radiation
HO2* - Answer✔hydroperoxyl radical
Germ cells - Answer✔Female and male reproductive cells
Radiation Biology - Answer✔branch of biology concerned with the effects of ionizing radiation
on living systems
Hydrogen Peroxide - Answer✔OH* + OH* = H2O2, a substance that is poisonous to the cell
Point Mutation - Answer✔Can result when ionizing radiation interacts with a DNA
macromolecule and the energy transferred in the process ruptures one of its chemical bonds
and serves one of the sugar phosphate chain side rails, or strands, of the ladderlike molecular
structure
H* and OH* - Answer✔A hydrogen radical and a hydroxyl radical
Radiation damage is observed on which of the following three levels?
A. Molecular, cellular, and inorganic systems
B. Molecular, cellular and organic systems
2
