Overview of Rad Bio Flashcards
Name the terms for interactions with matter
Ionization ( ejects electron from atom casing a charge)
Excitation (outer shell electron is exited but not ejected)
radiolysis
splitting
free radical
a highly reactive species with an unpaired valence outer shell electron ( symbolized by a dot)
LET
linear energy transfer
linear energy transfer
average energy deposited per unit path length
Direct ionization
occurs with dense ionization rad ( protons,
alpha particles)
high let radiation
fast electron directly ionizes the DNA molecule causing damage
indirect ionization
sparsely ionizing radiations ( x-ray and gamma)
damage to DNA molecules from splitting of H2O
free radicals are created by water splitting, highly reactive
2/3 of cellar damage is b/c of free radicals
H2O2 (hydrogen peroxide) is toxic to cell
secondary particles produced in the cell
mass and charge
linear energy transfer equation
energy deposited by keV divided by distance (micrometers)
relative biological effectiveness
the ability of radiation with different LET delivered under the same conditions to produce the same biologic effect
RBE equation
dose from 250 keV/ dose from test radiation to produce same biologic effect
sensitive area of DNA molecule
target
ionizing event that happens in the target
hit
pyrimidines
thymine and cytosine
purines
adenine and guanine
division delay
a disruption caused by irradiated cells
mitotic delay
process results in cells in interphase at the time of irradiation to be delayed in the g2 phase
fewer cells will enter the mitosis
radiosentizers
enhance response to radiation
radioprotectors
decrease response to radiation
OER
oxygen enhancement ratio
the magnitude of oxygen affect
interphase death (nonmitotic) (nondivision death)
irradiation of cell during G1, S, G2 phase results in death
VIM and DIM
vegetative intermitotic and differentiated intermitotic succumb interphase death in lower rad doses
(radiosensitive)
RPM and FPM
reverting post mitotic and fixed post mitotic occur with higher rad doses (radioresistant)
reproductive failure
also known as mitotic death unlimited number of divisions after radiation
