amber: Fossilized tree resin (not sap). Researchers think most of this gemstone likely comes from conifers, or evergreen trees that bear cones.
cell: The smallest structural and functional unit of an organism. Typically too small to see with the unaided eye, it consists of a watery fluid surrounded by a membrane or wall. Depending on their size, animals are made of anywhere from thousands to trillions of cells. Most organisms, such as yeasts, molds, bacteria and some algae, are composed of only one cell.
electric charge: The physical property responsible for electric force; it can be negative or positive.
electricity: A flow of charge, usually from the movement of negatively charged particles, called electrons.
mineral: Crystal-forming substances that make up rock, such as quartz, apatite or various carbonates. Most rocks contain several different minerals mish-mashed together. A mineral usually is solid and stable at room temperatures and has a specific formula, or recipe (with atoms occurring in certain proportions) and a specific crystalline structure (meaning that its atoms are organized in regular three-dimensional patterns). (in physiology) The same chemicals that are needed by the body to make and feed tissues to maintain health.
molecule: An electrically neutral group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in the air is made of two oxygen atoms (O2), but water is made of two hydrogen atoms and one oxygen atom (H2O).
particle: A minute amount of something.
piezoelectric: An adjective describing the ability of certain materials (such as crystals) to develop an electric voltage when deformed, or squeezed.
piezoelectricity: An electric discharge, often as a result of subtly deforming a crystal or crystalline material.
pressure: Force applied uniformly over a surface, measured as force per unit of area.
protein: A compound made from one or more long chains of amino acids. Proteins are an essential part of all living organisms. They form the basis of living cells, muscle and tissues; they also do the work inside of cells. Among the better-known, stand-alone proteins are the hemoglobin (in blood) and the antibodies (also in blood) that attempt to fight infections. Medicines frequently work by latching onto proteins.
resin: A sticky, sometimes aromatic substance, often secreted by plants. It may also be the viscous starting ingredient for some plastics that will harden when heated or treated with light.
sensor: A device that picks up information on physical or chemical conditions — such as temperature, barometric pressure, salinity, humidity, pH, light intensity or radiation — and stores or broadcasts that information. Scientists and engineers often rely on sensors to inform them of conditions that may change over time or that exist far from where a researcher can measure them directly. (in biology) The structure that an organism uses to sense attributes of its environment, such as heat, winds, chemicals, moisture, trauma or an attack by predators.
sound wave: A wave that transmits sound. Sound waves have alternating swaths of high and low pressure.
static: (in physics) An electronic signal that contains no information but does contain random fluctuations in intensity or wavelength.
static electricity: The buildup of excess electric charge on some surface instead of flowing through a material. This charge buildup tends to develop when two things that are not good conductors of electricity rub together. This allows electrons from one of the objects to be picked up and collected by the other.
wave: A disturbance or variation that travels through space and matter in a regular, oscillating fashion.