Overview of Radioactivity

<p>Nuclear medicine examinations (C)</p> Signup and view all the answers

<blockquote> <p>100 keV (B)</p> </blockquote> Signup and view all the answers

<p>The property of unstable atoms to emit nuclear radiation. (A)</p> Signup and view all the answers

<p>An atom with an excess of internal energy disrupting its nucleus. (D)</p> Signup and view all the answers

<p>Alpha particles and beta particles. (A)</p> Signup and view all the answers

<p>The disruptive forces outweigh the cohesive forces. (D)</p> Signup and view all the answers

<p>They are created through human activities. (D)</p> Signup and view all the answers

<p>Tc99-m (B)</p> Signup and view all the answers

<p>The time when both radioactive decay and biological elimination are present (C)</p> Signup and view all the answers

<p>The number of half-lives that have elapsed (B)</p> Signup and view all the answers

<p>It is shorter than both the biological and physical half-lives (D)</p> Signup and view all the answers

<p>Effective half-life is always less than physical half-life (D)</p> Signup and view all the answers

<p>They lose energy through interaction with matter. (C)</p> Signup and view all the answers

<p>Proton and beta particle. (B)</p> Signup and view all the answers

<p>Protons decay into neutrons with the emission of a beta particle. (D)</p> Signup and view all the answers

<p>A few millimeters. (D)</p> Signup and view all the answers

<p>It is converted into a neutron. (D)</p> Signup and view all the answers

<p>They can cause skin erythema if ingested. (C)</p> Signup and view all the answers

<p>Beta minus decay. (B)</p> Signup and view all the answers

<p>Beta minus decay. (C)</p> Signup and view all the answers

<p>Number of disintegrations per unit time (C)</p> Signup and view all the answers

<p>Becquerel (A)</p> Signup and view all the answers

<p>244,500 years (A)</p> Signup and view all the answers

<p>It represents the probability of a nucleus undergoing decay in a given time period. (A)</p> Signup and view all the answers

<p>15O (B)</p> Signup and view all the answers

<p>They provide a means to image anatomy and analyze physiological processes. (C)</p> Signup and view all the answers

<p>They have a lower decay constant. (C)</p> Signup and view all the answers

<p>It decreases over time. (D)</p> Signup and view all the answers

<p>An excess of neutrons or protons (C)</p> Signup and view all the answers

<p>Radioactive disintegration (B)</p> Signup and view all the answers

<p>Alpha decay (A)</p> Signup and view all the answers

<p>The number of protons and neutrons (A)</p> Signup and view all the answers

<p>They deposit energy over a short distance (D)</p> Signup and view all the answers

<p>Beta decay (B)</p> Signup and view all the answers

<p>It produces a daughter nuclide and an alpha particle (D)</p> Signup and view all the answers

<p>It can be stopped by a sheet of paper (D)</p> Signup and view all the answers

<p>20 (D)</p> Signup and view all the answers

<p>Nuclear transformation (C)</p> Signup and view all the answers

The spontaneous emission of nuclear radiation from the nucleus of an atom, usually alpha or beta particles, often accompanied by gamma rays.

Atoms with unstable nuclei that undergo radioactive decay.

The forces holding the nucleus together are weaker than the forces disrupting it.

Alpha particles are made of two protons and two neutrons. Beta particles are high-energy electrons (or positrons). Gamma rays are high-energy photons.

Alpha decay, Beta decay, Gamma decay.

A type of radioactive decay in which a neutron in the nucleus decays into a proton, an electron (beta particle), and an antineutrino.

A particle with no charge and nearly zero mass, emitted during beta decay. It interacts very weakly with matter.

A type of radioactive decay in which an excited nucleus emits a high-energy photon, called a gamma ray, to return to a lower energy state.

An atom with the same atomic number but different energy levels. Often formed after alpha or beta decay.

A high-energy photon emitted during gamma decay, traveling at the speed of light. One of the most energetic forms of electromagnetic radiation.

The process of an unstable nucleus transforming into a stable form by emitting particles or energy. Also known as 'nuclear transformation' or 'radioactive decay'.

An atom with an unstable nucleus that undergoes radioactive disintegration. It's also referred to as a 'radionuclide' or 'radioisotope'.

A type of radioactive decay where an unstable nucleus emits an alpha particle (two protons and two neutrons).

A heavy, slow-moving particle consisting of two protons and two neutrons, emitted during alpha decay.

The resulting nucleus after an alpha decay, which is lighter than the original nucleus.

The nucleus that undergoes radioactive decay, for example, undergoing alpha decay.

High-energy electrons or positrons emitted during beta decay.

A type of radioactive decay where an unstable nucleus captures an inner-shell electron, resulting in the emission of a gamma ray.

High-energy electromagnetic radiation emitted during different types of radioactive decay, including electron capture and gamma decay.

Beta particles are emitted from nuclei that have too many neutrons for stability. This occurs when a neutron in the nucleus decays into a proton and an electron, releasing an electron (beta minus) and a proton which rejoins the nucleus.

Beta particles are emitted from nuclei that have too many protons for stability. This occurs when a proton in the nucleus decays into a neutron and a positron, releasing a positron (beta plus) and a neutron which rejoins the nucleus.

The energy that a particle can deposit in living tissue. It can cause significant damage to cells.

Measure of the radiation energy deposited in living tissue per unit mass. It's the energy absorbed by the tissue.

A measure of the radiation energy deposited per unit mass of a material while considering the specific type of radiation and the biological effectiveness of the radiation.

Radiation that can penetrate a few centimeters of tissue and cause skin reddening or erythema.

The emission of negatively charged beta particles. This occurs when a neutron in the nucleus decays into a proton and an electron.

The process of using a gamma camera to measure the amount of a radioactive substance absorbed in different parts of the body.

Technetium-99m is a common radioactive isotope used in medical imaging, especially bone scans. It has a half-life of 6 hours, which means its radioactivity decreases by half every six hours.

A bone scan often combines the images from a gamma camera with those from a CT scan to provide a more comprehensive picture of bone health.

The effective half-life is the time it takes for the amount of a radioactive substance in the body to reduce by half due to a combination of radioactive decay and biological elimination processes.

Calculating the amount of radioactive substance remaining at a given time is done using the formula A = A0 / (2^N) where A is the activity at a given time, A0 is the initial activity, and N is the number of half-lives that have passed since the initial activity.

The time taken for the activity of a radioactive substance to decrease to half its initial value. It's a constant for each radionuclide.

The number of radioactive decays per unit time. It's how we measure the 'strength' of a radioactive sample.

Activity per unit mass of a radioactive substance. It's a useful way to compare how 'radioactive' different materials are.

The probability that a radioactive nucleus will decay in a given time period. It's a key factor in understanding radioactive decay.

A curve that shows the gradual decrease of radioactivity over time for a specific radionuclide.

A radioactive substance used in nuclear medicine to image the body and analyze physiological processes.

A branch of medicine that uses radioactive substances to diagnose and treat diseases.

A process that involves using radioactive substances to create images of the inside of the body.