action potential: A brief change in the electrical potential on the surface of a cell, especially of a nerve or muscle cell. It happens when the cell is stimulated. This triggers the release of an electrical impulse. 

agriculture: The growth of plants, animals or fungi for human needs, including food, fuel, chemicals and medicine. 

cell: (in biology) 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.  

chemical: A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H₂O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds. 

crop: (in agriculture) A type of plant grown intentionally grown and nurtured by farmers, such as corn, coffee or tomatoes. Or the term could apply to the part of the plant harvested and sold by farmers. 

cultivate: To prepare land for growing food or to nurture the growth of a plant. 

current: A fluid — such as of water or air — that moves in a recognizable direction. (in electricity) The flow of electricity or the amount of charge moving through some material over a particular period of time. 

deciduous: (in botany) Those trees and shrubs that lose their leaves in winter, each year, then grow new ones the next spring. 

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. 

electrode: A device that conducts electricity and is used to make contact with the non-metal part of an electrical circuit, or that contacts something through which an electrical signal moves. (in electronics) Part of a semiconductor device (such as a transistor) that either releases or collects electrons (negative charges) or holes (positive charges) — or that can control their movement. 

electronics: Devices that are powered by electricity but whose properties are controlled by the semiconductors or other circuitry that channel or gate the movement of electric charges. 

engineer: A person who uses science and math to solve problems. As a verb, to engineer means to design a device, material or process that will solve some problem or unmet need. 

environment: The sum of all of the things that exist around some organism or the process and the condition those things create. Environment may refer to the weather and ecosystem in which some animal lives, or, perhaps, the temperature and humidity (or even the placement of things in the vicinity of an item of interest). 

fungi: (sing: fungus) Organisms with one or more cells that reproduce via spores and feed on living or decaying organic matter. Examples include mold, yeasts and mushrooms. 

gait: The pattern of leg motions by which an animal walks from place to place. 

materials scientist: A researcher who studies how the atomic and molecular structure of a material is related to its overall properties. Materials scientists can design new materials or analyze existing ones. Their analyses of a material’s overall properties (such as density, strength and melting point) can help engineers and other researchers select materials that are best suited to a new application. 

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). 

nerve: A long, delicate fiber that transmits signals across the body of an animal. An animal’s backbone contains many nerves, some of which control the movement of its legs or fins, and some of which convey sensations such as hot, cold or pain. 

nutrient: A vitamin, mineral, fat, carbohydrate or protein that a plant, animal or other organism requires as part of its food in order to survive. 

oxygen: A gas that makes up about 21 percent of Earth’s atmosphere. All animals and many microorganisms need oxygen to fuel their growth (and metabolism). 

plastic: Any of a series of materials that are easily deformable; or synthetic materials that have been made from polymers (long strings of some building-block molecule) that tend to be lightweight, inexpensive and resistant to degradation.  

potential energy: The energy held by an object due not to its motion but instead to its position or condition (such as being held motionless by a brake or suspended from a wire). Examples of objects possessing this type of energy include a compressed spring or a mass of snow on a hillside (think of its capacity to create an avalanche). 

robot: A machine that can sense its environment, process information and respond with specific actions. Some robots can act without any human input, while others are guided by a human. 

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. 

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. 

synthetic: An adjective that describes something that did not arise naturally, but was instead created by people. Many synthetic materials have been developed to stand in for natural materials, such as synthetic rubber, synthetic diamond or a synthetic hormone. Some may even have a chemical makeup and structure identical to the original. 

taste: One of the basic properties the body uses to sense its environment, especially foods, using receptors (taste buds) on the tongue (and some other organs). 

technology: The application of scientific knowledge for practical purposes, especially in industry — or the devices, processes and systems that result from those efforts. 

transparent: Allowing light to pass through so that objects behind can be distinctly seen. Or information that lets others understand the otherwise hidden people, processes and impacts behind some product, action or proposal. 

ultraviolet: A portion of the light spectrum that is close to violet but invisible to the human eye. 

ultraviolet light: A type of electromagnetic radiation with a wavelength from 10 nanometers to 380 nanometers. The wavelengths are shorter than that of visible light but longer than X-rays.