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angle The space (usually measured in degrees) between two intersecting lines or surfaces at or close to the point where they meet.
antigen A substance capable of causing an immune reaction.
carbon dioxide (or CO2) A colorless, odorless gas produced by all animals when the oxygen they inhale reacts with the carbon-rich foods that they’ve eaten. Carbon dioxide also is released when organic matter burns (including fossil fuels like oil or gas). Carbon dioxide acts as a greenhouse gas, trapping heat in Earth’s atmosphere. Plants convert carbon dioxide into oxygen during photosynthesis, the process they use to make their own food.
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.
clot (in medicine) A collection of blood cells (platelets) and chemicals that collect in a small region, stopping the flow of blood.
discriminate (n. discrimination) The detection or recognition of a difference between two or more versions of something.
emergency medical technician (abbr. EMT) A heath care provider who serves in times of emergency. They are not doctors or nurses. They are trained to respond quickly to emergency situations to aid a patient until a doctor or nurse can see them. They often work in ambulances and are sometimes called paramedics.
engineering The field of research that uses math and science to solve practical problems.
gene (adj. genetic) A segment of DNA that codes, or holds instructions, for a cell’s production of a protein. Offspring inherit genes from their parents. Genes influence how an organism looks and behaves.
immune system The collection of cells and their responses that help the body fight off infections and deal with foreign substances that may provoke allergies.
infection A disease that can spread from one organism to another. It’s usually caused by some type of germ.
infrared light A type of electromagnetic radiation invisible to the human eye. The name incorporates a Latin term and means “below red.” Infrared light has wavelengths longer than those visible to humans. Other invisible wavelengths include X-rays, radio waves and microwaves. Infrared light tends to record the heat signature of an object or environment.
Intel International Science and Engineering Fair (Intel ISEF) Initially launched in 1950, this competition is one of three created (and still run) by the Society for Science & the Public. Each year now, approximately 1,800 high school students from more than 75 countries, regions, and territories are awarded the opportunity to showcase their independent research at Intel ISEF and compete for an average of $4 million in prizes.
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).
platelets The smallest of blood cells, their role is to hunt for signs that a blood vessel has been damaged. Then the platelets congregate at the site of damage and transform themselves, growing long tentacles. There, they link together, creating a clot to plug any hole. This should help stem the potential loss of blood.
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.
radio waves Waves in a part of the electromagnetic spectrum. They are a type that people now use for long-distance communication. Longer than the waves of visible light, radio waves are used to transmit radio and television signals. They also are used in radar.
red blood cell A type colored red by hemoglobin. These cells move oxygen from the lungs to all tissues of the body. Red blood cells are too small to be seen by the unaided eye.
Rh An antigen on the surface of red blood cells in most people. People whose blood cells have it are said to have an “Rh-positive” type. The others are “Rh-negative.” The Rh stands for rhesus, the type of monkey in which this antigen was first observed. Before someone can safely receive a blood transfusion, the general type of blood — A, B, AB or O — must match, as well as this Rh factor.
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.
tissue Made of cells, any of the distinct types of materials that make up animals, plants or fungi. Cells within a tissue work as a unit to perform a particular function in living organisms. Different organs of the human body, for instance, often are made from many different types of tissues.
wavelength The distance between one peak and the next in a series of waves, or the distance between one trough and the next. Radiation with wavelengths longer than visible light includes infrared light, microwaves and radio waves.
white blood cells Blood cells that help the body fight off infection.