Ch 4-6 Flashcards
(323 cards)
Radiation quantity “that expresses the concentration of radiation delivered to a specific area, such as the surface of the human body” The amount of ionizing radiation that may strike an object such as the human body when in the vicinity of a radiation source Amount of radiation in air When a volume of air is irradiated with x-rays or gamma rays, the interaction that occurs between the radiation and neutral atoms in the air causes some electrons to be liberated from those air atoms as they are ionized. Consequently, the ionized air can function as a conductor and carry electricity because of the negatively charged free electrons and positively charged ions that have been created. As the intensity of x-ray exposure of the air volume increases, the number of electron-ion pairs produced also increases. Thus the amount of radiation responsible for the ionization of a well-defined volume of air may be determined by measuring the number of electron-ion pairs or charged particles in that volume of air; radiation ionization in the air A measure of ionization in air and not in other tissue
Exposure (X)
The breaking down of large molecules into smaller ones through the process of oxidation
Oxidative metabolism
What does the OSL dosimeter contain?
A thin layer of aluminum oxide (Al2O3) detector
6 late deterministic somatic effects
Cataract formation Fibrosis Organ atrophy Loss of parenchymal cells Reduced fertility Sterility
3 processes the protoplasm carries on
Complex process of metabolism Reception and processing of food and oxygen Elimination of waste products
1 SI exposure unit equals
C/kg = 1/(2.58 x 10^-4) R
Cells manufacture certain proteins and RNA molecules need to enter and complete the next mitosis When this phase is complete, cells enter the first phase of mitosis (prophase)
G2 (post-DNA synthesis phase)
What is the film badge dosimeter sensitivity?
Most sensitive to photons having an energy level of 50 keV; for values above and below this energy range, dosimetry film sensitivity decreases
What is the equation to determine one gray?
1 Gy = 1 J/kg
Equation of effective dose (EfD)
EfD = absorbed dose (D) x radiation weighting factor (WR) x tissue weighting factor (WT)
3 main parts the cell contains
Cell membrane Cytoplasm Nucleus
The aluminum filter of the OSL dosimeter offers the ______ absorption, whereas the copper filter attenuates the _______
Least, most
Very small spherical organelles that attach to the ER “Protein factories”; their job is to manufacture (synthesize) the various proteins that cells require by using the blueprints provided by the mRNA
Ribosomes
Unit of EfD
Sieverts or millisieverts
Do you want a high or low LET?
Low
Where should the personnel dosimeter be placed during routine radiographic procedures when a protective apron is not being used?
Attached to the clothing on the front of the body at collar level
Biologic effects in humans caused by exposure to ionizing radiation, which appeared within minutes, hours, days, or weeks of the time of radiation exposure
Early deterministic somatic effects
Effect of radiation that is seen in an individual and in subsequent unexposed generations
Genetic/heritable effects
Sugars that have two units of a simple sugar linked together; ex: lactose, sucrose (cane sugar)
Disaccharides
Chemical building material for all living things; living contents of cell
Protoplasm
To what exposure range are pocket chambers used in medical imaging sensitive to?
0-5.2 x 10^-5 C/kg (0-200 mR)
6 functions that lipids perform for the body
Acts as a reservoir for the long-term storage of energy Insulate and guard the body against the environment Support and protect organs such as the eyes and kidneys Provide essential substances necessary for growth and development Lubricate the joints Assist in the digestive process
When is exposure monitoring or personnel required?
Whenever radiation workers are likely to risk receiving 10% or more of the annual occupational EfD limit of 50 mSv (5 rem) in any single year as a consequence of their work related activities
8 important electrolytes in the body
Sodium (Na+) Potassium (K+) Calcium (Ca++) Magnesium (Mg++) Chloride (Cl-) Bicarbonate (HCO3-) Phosphate (HPO4-) Sulfate (SO4-2)