BASIC RADIOBIOLOGY Flashcards
- a branch of science which combines the basic principles of physics and biology
- is concerned with the action of ionizing radiation on biological tissues and living organisms
RADIOBIOLOGY
All living entities are made up of?
PROTOPLASM
basic microscopic unit of all living organisms
CELL
Group of cells that together perform one or more functions is referred to
TISSUE
Group of tissues that together perform one or more functions is
called
ORGAN
Group of organs:
ORGAN SYSTEM
either a sperm or an egg
GERM CELLS
all other human cells
SOMATIC CELLS
- division of somatic cells
- results in two genetically identical daughter cells
MITOSIS
- division of germ cells
- involves two fissions of the nucleus
giving rise to four sex cells, each possessing half the number of chromosomes of the original germ cell
MEIOSIS
Somatic cells are classified as:
STEM CELLS
TRANSIT CELLS
MATURE CELLS
Dose is delivered continuously but at a lower dose rate
Protraction
Dose is delivered at the same dose rate, in equal fractions, separated by 24 hours
Fractionation
Tissue is more sensitive when…
Irradiated in the oxygenated state than when irradiated without oxygen
Aerobic
Oxygenated
Anoxic
Without oxygen
Hypoxic
Low oxygen
Cell dies before replicating
Interphase death
Halogenated pyrimidines, methotrexate, acitinomycin D, hydroxurea, and vitamin K
Types of sensitizing agents
Some studies show that a little bit of radiation is good for you
Hormesis
_____ is a measure of the rate that energy is transferred from ionizing radiation to soft tissue
LET
As LET _____ the RBE _______
Increases, increases
Early effects/events
Normally occurs within days or minutes after the radiation exposure
DETERMINISTIC EFFECT
Late effects/events
Normally occurs within months or years
STOCHASTIC EFFECT
