Visionlearning Glossary

French zoologist and botanist, born in Bazentine le Petit (1744-1829). While working as a professor of invertebrate natural history at the Musée National d'Histoire Naturelle, Lamarck developed his theory of evolution, which stated that organisms could change in response to changes in their environment and could pass these changes on to their offspring, a theory later proven largely incorrect. For further information see Jean Baptiste Lamarck.

Used in the following modules: Adaptation

French mathematician and astronomer born in Normandy, France (1749-1827). Laplace made significant contributions in mathematics and error quantification and is credited with founding the field of mathematical astronomy. In addition, he predicted the existence of black holes and the concept of gravitational collapse. For more information, see Pierre-Simon Laplace.

Used in the following modules: Data: Uncertainty, Error, and Confidence

A characteristic pattern formed by the spatial distribution of repeating units.

Used in the following modules: Water

French chemist, born in Paris (1743-1794). He is famous for proving that air is composed of several gases - he thought 2. He also experimentally established the Law of Conservation of Mass, devised the system of chemical nomenclature that is currently in use, and authored the first modern chemistry textbook, Traité Élémenaire de Chimie (Elementary Treatise of Chemistry). For further information see Antoine Lavoisier.

Used in the following modules: Matter

English gentleman farmer, born at the Rothamsted Manor House in Hertfordshire (1814-1900). He investigated the effects of various fertilizers on crops. Rothamsted Station is still now the oldest functioning agricultural research station in the world, and some experiments (termed Rothamstead Classical Experiments) have been running since it was founded. For further information, see John Bennet Lawes.

Used in the following modules: Data: Statistics

French astronomer, born in Saint-Lô, (1811-1877). He worked primarily on celestial mechanics and, like John Couch Adams, predicted the existence of Neptune based on perturbations in the orbit of Uranus. He also—incorrectly—predicted the existence of a planet inside the orbit of Mercury, which he named Vulcan, based on perturbations in Mercury’s orbit. For further information, see Urbain Le Verrier.

Used in the following modules: Gravity

Dissolving out by the action of a percolating liquid.

French mathematician, naturalist and biologist, born in Montbard, Côte-d’Or (1707-1788). In 1727, Leclerc discovered the binomial theorem. In the 1730’s, he published Mémoire sur le jeu de franc-carreau (Thesis on the game of franc-carreau), which combined differential and integral calculus with probability theory. His most famous works are in natural history, where his ideas influenced the thinking of Lamarck and Darwin. His great work, Histoire naturelle, générale et particulière (General and specific natural history) consists of 36 volumes, published in 1749-1778, plus 8 more volumes published after his death. For more information, see earthquakes and explosions and the microseismic wave motions generated by Arctic and North Sea storms. From refractions of seismic waves, she discovered the Earth’s inner core 1936. In 1971, Lehmann was awarded the Bowie Medal by the American Geophysical Union for her contributions to the fields of seismology and earth science. For more information, see Inge Lehmann.

Used in the following modules: Earth Structure

Shaped like a lens, of or related to a lens; often referring to clouds, galaxies, rock bodies, or small features within rocks.

Used in the following modules: Research Methods: Description

American chemist born in Weymouth, Massachusetts (1875-1946). Lewis’s early work, carried out as a faculty member at MIT, involved the determination of electrode potentials of elements, conductivity and thermodynamics. Most of his later work focused on thermodynamics and chemical equilibrium, electron-pair bonding of atoms and molecules, isotopes, and light-matter interactions. During his 34-year tenure at UC Berkeley, Lewis was renowned as a remarkable teacher and advisor. In 1923 he published Valence and the Structure of Atoms and Molecules, still considered a classic work and a vital contribution to modern bonding theory. For more information see Gilbert Newton Lewis.

Used in the following modules: Chemical Bonding

A form of electromagnetic radiation. Visible light is that associated with stimulating the organs of sight, which for normal human vision ranges in wavelength from 3900 to 7700 ångstroms.

Used in the following modules: Atomic Theory II, Cells, Charles Darwin I, Chemical Equations, Chemical Reactions, Data: Using Graphs and Visual Data, DNA I, Educational Web Design, Energy, Genetics I, Gravity, Light I, Light II, Matter: States of Matter, Minerals II, Minerals III, Nuclear Chemistry, Research Methods: Comparison, Research Methods: Experimentation, Research Methods: Modeling, Research Methods: The Practice of Science, Scientific Communication: Peer Review, Scientific Communication: Understanding Scientific Journals and Articles, The Carbon Cycle, Wave Mathematics

A sedimentary rock composed mainly of calcite (CaCO₃). Limestone forms through chemical precipitation in warm, shallow seas, and often contains marine fossils.

Used in the following modules: Plate Tectonics I, The Carbon Cycle

A reactant that limits the amount of product produced in a chemical reaction.

An emission spectrum of light that contains very sharply defined lines. Line spectra are given off when matter is heated or excited in some way and each line corresponds to a wavelength of light given off during an electron transition from an excited state to the ground state.

Used in the following modules: Atomic Theory II, Data: Using Graphs and Visual Data

The seven major categories of biological classification based on Linnaeus’ system: Kingdom, Phylum, Class, Order, Family, Genus, and Species.

(also Carl Linnaeus or Karl von Linné) Swedish physician, naturalist and taxonomist born in Stenbrohult (1707-1778). Inspired by the work of John Ray, Linnaeus developed a system for classifying organisms, a modified version of which is still in use. In 1735, he published the first edition of Systema Naturae, which detailed his classification system. He was also the physician to the Royal Family of Sweden. For more information see Carolus Linnaeus.

Used in the following modules: Taxonomy I, Taxonomy II: Nomenclature

A diverse group of organic molecules that contain long hydrocarbon chains or rings and are hydrophobic. Examples are fats, oils, waxes, and steroids.

Used in the following modules: DNA I, Fats and Proteins

The rigid upper layer of the earth consisting of the crust and the upper mantle. The earth’s tectonic plates are composed of pieces of the lithosphere. The lithosphere ranges in thickness from 10-12 km underneath the oceans to 70-200 km at the continents.

Used in the following modules: Earth Structure

Austrian chemist and physicist, born in Pocerny (now part of the Czech Republic) (1821-1895). He worked in thermodynamics, optics and electrodynamics. One of his many contributions to science was the accurate calculation of the average size of the gas molecules that make up air. For further information see Johann Josef Loschmidt.

Used in the following modules: The Mole

British chemist, born in Letchworth Garden City (1919-). He developed the Gaia Hypothesis, which proposes that the biosphere and all physical components of the Earth are coupled together in a complexly interacting system. The hypothesis is frequently paraphrased as describing the Earth as a single living organism. Lovelock was also an inventor: his most famous invention is the electron capture detector, which provided valuable information on the distribution of halogen-bearing chemicals and CFCs in the atmosphere. For further information see James Lovelock.

Used in the following modules: Research Methods: The Practice of Science

A celestial event occurring when the Moon passes through some portion of the Earth's shadow. This only occurs when the Sun, Earth, and Moon are aligned so that the Earth is between the Sun and the Moon.

Used in the following modules: Research Methods: Description, Scientific Communication: Utilizing the Scientific Literature

A British geologist born in Scotland (1797-1875 CE). His most important work was The Principles of Geology: An Attempt to Explain the Former Changes of the Earth's Surface by Reference to Causes now in Operation. Lyell championed the theory of uniformitarianism, which states that the same processes we see on Earth today were active throughout the past and shaped the earth as we know it, including slow processes like sedimentation. This opposed the leading view at that time, catastrophism, which states that changes to the earth’s surface occur in sudden, discrete events. He also wrote Elements of Geology, which is still considered a seminal work on stratigraphy and paleontology. His third major, though now lesser known, work was The Antiquity of Man, in which he supports Darwin’s theories regarding the origins of species. The Lyell Medal is now awarded yearly by the Council of the Geological Society to a significant contemporary geologist. For further information see Charles Lyell; also see our module The Rock Cycle.

Used in the following modules: Charles Darwin II