Answers Already Passed
What is the primary function of the cell membrane?
✔✔ To regulate the movement of substances in and out of the cell.
What are chromosomes made of?
✔✔ DNA and proteins.
What is the most radiosensitive phase of the cell cycle?
✔✔ The M phase (mitosis).
What is the unit used to measure absorbed radiation dose?
✔✔ Gray (Gy).
What is the most common effect of radiation on cells?
✔✔ Damage to DNA.
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,Which type of radiation is the most penetrating?
✔✔ Gamma rays.
What is the primary component of an atom?
✔✔ Protons, neutrons, and electrons.
What type of radiation interaction is most significant in diagnostic radiology?
✔✔ Photoelectric effect.
What does ALARA stand for?
✔✔ As Low As Reasonably Achievable.
What organ system is most affected by whole-body exposure to high doses of radiation?
✔✔ The hematopoietic system.
What is the threshold dose for erythema?
✔✔ Approximately 2 Gy.
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,What are free radicals, and why are they important in radiation biology?
✔✔ Unstable molecules formed by radiation that can damage cellular components.
What is a deterministic effect of radiation?
✔✔ An effect that increases in severity with dose, such as skin burns.
What is a stochastic effect of radiation?
✔✔ An effect that increases in probability with dose, such as cancer.
What is the primary function of DNA in cells?
✔✔ To store and transmit genetic information.
What is the half-life of a radioactive substance?
✔✔ The time it takes for half of the radioactive atoms to decay.
What is radiolysis?
✔✔ The splitting of water molecules by ionizing radiation.
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, What type of cells are most radiosensitive?
✔✔ Rapidly dividing cells, such as stem cells and lymphocytes.
What is the purpose of a dosimeter?
✔✔ To measure exposure to ionizing radiation.
What is the LD50/30 for humans?
✔✔ Approximately 3 to 4 Gy.
What is the oxygen enhancement ratio (OER)?
✔✔ The ratio of radiation dose required to produce an effect under anoxic conditions to the dose
required under oxygenated conditions.
What is the main source of natural background radiation?
✔✔ Radon gas.
What is the primary goal of radiation protection?
✔✔ To minimize unnecessary radiation exposure to humans and the environment.
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