Ionizing events from irradiation are considered to be direct effects if they occur with
___________ molecules.
- water
- DNA
- protein
- Both A and B correct answers DNA
Fractionation and protraction are used for radiation therapy because they allow the patient to
- have higher total doses.
- repair damaged tissues.
- recover between doses.
- All of the above. correct answers All of the above.
The method that is used to determine the volume of tissue that needs to be included in the
radiation field is called:
- brachytherapy
- simulation
- dosimetry
- linear energy transfer correct answers simulation
When radiographic images are produced during portal imaging using megavoltages,
- high contrast images are produced due to the number of photoelectric interactions.
- pair production and Compton interactions predominate.
- very low contrast images are produced.
- both b and c correct answers both b and c
,The LD50/30 is representative of the dose:
- Necessary to kill 50% of the cells in 30 days
- Necessary to kill 50% of the cells in 50 days
- Necessary to kill 10% of the cells in 50 days
- Necessary to kill 30% of the cells in 50 days correct answers Necessary to kill 50% of the cells
in 30 days
The human body is composed of about 80% ______________.
- protein
- water
- carbohydrates
- nucleic acids correct answers water
The disassociation of water molecules following irradiation is termed _____________.
- ionization
- cross-linking
- point mutation
- radiolysis correct answers radiolysis
The process of cell division of somatic cells is known as:
- Mitosis
- Synthesis
- Reduction division
- Meiosis correct answers Mitosis
The goal of radiation oncology is to:
- deliver a large dose all at once to the cancer
, - destroy all tissue in the portion of the body where the cancer is located
- deliver a cancericidal dose to the tumor but limit the dose to normal tissue
- limit dose to the cancer and normal tissue to avoid toxicity correct answers deliver a
cancericidal dose to the tumor but limit the dose to normal tissue
A dose of 1000 rads given to a patient in five doses of 200 rads per day is a ____ dose.
- fractionated
- protracted
- fatal
- diagnostic correct answers fractionated
How many matched pairs of chromosomes does a normal human cell contain?
- 23
- 11 correct answers 23
The possible beneficial effect of a small amount of radiation is called ____________.
- hormesis
- protraction
- radiosensitizing
- radioprotection correct answers hormesis
The mean lethal dose for high-LET radiation is _______ than after low-LET radiation.
- lower
- the same
- unknown
- higher correct answers lower