Radiation Biology Flashcards

Flashcards about Radiation Biology

Radiation Biology

The study of the effects of radiation on living tissue.

Ionizing Radiation

Radiation capable of changing the chemical state of matter, causing biological damage, and potentially harmful to human health (e.g., alpha, beta, and gamma radiation).

Non-ionizing Radiation

Radiation that bounces off or passes through matter without displacing electrons (e.g., visible light and radio waves).

Alpha Particle

A type of radiation consisting of two protons and two neutrons; it's heavy, has a large charge, doesn't travel far, and can be harmful if inhaled or ingested.

Beta Particle

An electron that is not attached to an atom; it has a small mass, a negative charge, travels farther than alpha particles, and can penetrate the body but not all the way through.

Neutron

A particle with no charge present in the nucleus of an atom; it travels a long way and requires large quantities of water or light atoms to stop.

Electromagnetic Radiation

Radiation like X-rays and gamma rays that has energy but no mass or charge; it can penetrate the body.

Radioisotopes

Radioactive isotopes of an element with an unstable combination of neutrons and protons or excess energy in their nucleus.

Radioactive Decay

The process by which atoms with an unstable nucleus regain stability by shedding excess particles and energy in the form of radiation.

Half-life

The time it takes for half of the unstable atoms in a radioisotope to undergo radioactive decay.

Direct Effects (Radiation Injury)

Radiation interacts directly with the atoms of the DNA molecule or other critical cellular component, affecting a cell's ability to reproduce and survive.

Indirect Effects (Radiation Injury)

Ionizing radiation breaks the bonds of water molecules, producing toxic radicals that can destroy the cell.

Prodromal Period

The initial stage of radiation injury, characterized by symptoms like nausea, vomiting, loss of appetite, and diarrhea, occurring minutes to days after exposure.

Latent Period

The time between exposure to radiation and the appearance of radiation damage.

Mitotic Death

Cells die attempting to divide, primarily due to asymmetric chromosome anomalies; this is the most common mechanism of cell death after irradiation.

Apoptosis

Programmed cell death characterized by a sequence of events resulting in cell separation in apoptotic bodies.

Bystander Effect

Cells directly affected by radiation release cytotoxic molecules causing death in neighboring cells.

Single-Strand Breaks

Breaks in one strand of DNA that are typically easily repaired using the opposite strand as a template.

Double-Strand Breaks

Breaks in both strands of DNA that are considered the most important lesions produced by radiation and can lead to cell killing.

Diagnostic Radiology

The use of X-rays to produce anatomical or functional patient images while delivering the lowest possible radiation dose.

Nuclear Medicine

The use of radioactive isotopes as tracers to track their distribution in the body for diagnostic or treatment purposes.

Radiotherapy

The treatment of cancer and other conditions involving abnormal tissue growth by bombarding the tissue with ionizing radiation.

Somatic Effects

Effects of radiation that occur in all cells of the body except reproductive cells and are not passed on to future generations.

Genetic Effects

Effects of radiation that occur in reproductive cells and are passed on to future generations through mutations.