Visionlearning Glossary

The basis, procedures and rules for naming and classifying organisms.

Used in the following modules: Charles Darwin I, Charles Darwin III, Taxonomy I, Taxonomy II: Nomenclature

The regions of the earth that lie between the Tropic of Cancer (~23° N) and the Arctic Circle (~66° N) in the Northern Hemisphere and the Tropic of Capricorn (~23° S) and the Antarctic Circle (~66° S) in the Southern Hemisphere. The climate of these regions, though not mild, avoids the extremes of hot and cold found in lower and higher latitudes.

Greek philosopher born in Miletus (ca. 624-546 BCE). Thales was a pre-Socratic philosopher, one of the Seven Sages of Greece. Herodotus reports that Thales predicted a solar eclipse in 585 BCE, thus ending a war between the Lydians and Medes. Thales’ philosophy was founded on the belief that water, one of the four elements, is the origin and ultimate end of all things. For further information see Thales.

Used in the following modules: Matter: States of Matter

The outermost layer of the atmosphere, where gas molecules split apart into ions.

Used in the following modules: Earth's Atmosphere

English physicist born in Manchester (1856-1940). In 1884, Thomson won the Adams Prize for his Treatise on the Motion of Vortex Rings, which concerns atomic structure. His most famous work was a study of cathode rays, which resulted in his discovery of the electron and the existence of isotopes. For this he was awarded the Nobel Prize in Physics in 1906. For further information see John Thomson.

Italian mathematician and astronomer, born in Faenza, Italy (1608-1647). He authored Torricelli’s Theorem, which states that the flow of liquid through an opening is proportional to the square root of the height of the liquid. Torricelli also experimentally proved that air has weight, and invented the barometer. His work is somewhat obscure today, in part because he only published one work, Opera Geometrica. For further information see Evangelista Torricelli.

Used in the following modules: Earth's Atmosphere, Matter

A fine-grained volcanic rock consisting predominantly of alkali feldspar and one or more subordinate minerals, generally hornblende or mica.

Used in the following modules: Research Methods: Description

A plate boundary where two plates are sliding past each other.

Used in the following modules: Plate Tectonics II

The transfer of water vapor into the air from plants, often called evapotranspiration.

Used in the following modules: The Hydrologic Cycle

In science, a treatment refers to a method for fixing or manipulating an independent variable in the course of scientific research. For more information, see: Research Methods: Experimentation

Used in the following modules: Data: Statistics, Data: Uncertainty, Error, and Confidence, Research Methods: Comparison, Research Methods: Experimentation, Research Methods: The Practice of Science, Scientific Communication: Peer Review, Scientific Communication: Understanding Scientific Journals and Articles

In plate tectonics, trenches are tremendously deep features on the ocean floor—deep valleys that reach as far as 11 km below sea level. These trenches are the edge of subduction zones, where one plate is diving beneath another.  

Used in the following modules: Plate Tectonics II, The Rock Cycle

The lowermost 12-18 km of the atmosphere, where temperature decreases about 6.5 degrees Celsius per kilometer of altitude. Wind, precipitation, and the jet stream all occur within the troposphere.

Used in the following modules: Earth's Atmosphere, Research Methods: The Practice of Science

English physician born in Clevedon, Somerset (1650-1708). His most famous work was Orang-Outang, sive Homo Sylvestris; or, the Anatomy of a Pygmie Compared with that of a Monkey, an Ape, and a Man. He was physician and governor of the first mental hospital in Britain, the Bethlem Hospital in London, and is considered to be the founder of comparative anatomy. For further information, see Edward Tyson.

Used in the following modules: Research Methods: Comparison