[person - evolution & adaptation, scientific concepts] 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.

• Appears in modules:

• Adaptation

[noun - landforms & geologic formations] The natural scenery of a region; a collection of landforms in an area.

• Appears in modules:

• Craig Lee
• Description in Scientific Research
• Modeling in Scientific Research
• Sergio Avila
• The Hydrologic Cycle
• The Rock Cycle

[person - anatomy & physiology, medicine] (1868-1943) Austrian forensic researcher and physician who discovered ABO blood types in 1900, thereby enabling safe blood transfusion. Also, together with Alexander Wiener in 1937, he discovered the Rh antigen and three years later the role of Rh in pregnancy complications resulting from the mismatch between Rh typing of a mother and her fetus.

• Appears in modules:

• Blood Biology I

[acronym - atoms & subatomic particles] Los Alamos National Laboratory

• Appears in modules:

• Scientific Institutions and Societies

[person - research tools, fundamental constants] 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.

• Appears in modules:

• Introduction to Descriptive Statistics
• Uncertainty, Error, and Confidence

[noun - scientific tools & techniques] A characteristic pattern formed by the spatial distribution of repeating units.

• Appears in modules:

• Chemical Bonding
• Properties of Solids

[person - energy, matter, scientific concepts] French chemist, born in Paris (1743-1794). He is famous for proving that air is composed of several gases. 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).

• Appears in modules:

• Atomic Theory II
• Chemical Equations
• Early Ideas about Matter
• Kinetic-Molecular Theory
• Thermodynamics I

[noun] In science, a principle that describes a phenomenon, often mathematically.

• Appears in modules:

• Animal Behavior
• Atomic Theory I
• Atomic Theory III
• Charles Darwin I
• Chemical Equations
• Creativity in Science
• Defining Minerals
• Diffusion I
• DNA I
• DNA II
• Early Ideas about Matter
• Energy
• Gene Expression
• Gravity
• Kinetic-Molecular Theory
• Light and Electromagnetism
• Light I
• Mario Molina
• Mendel and Independent Assortment
• Mendel and Inheritance
• Population Genetics
• Properties of Minerals
• Scientific Ethics
• Scientific Institutions and Societies
• The Nature of Scientific Knowledge
• The Phosphorus Cycle
• The Practice of Science
• The Silicate Minerals
• Theories, Hypotheses, and Laws
• Thermodynamics I
• Understanding Scientific Journals and Articles

[person - rocks & minerals, data, scientific concepts] 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.

• Appears in modules:

• Statistics in Science

[person - planetary science] 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.

• Appears in modules:

• Gravity

[verb - hydrology & fresh water, rock cycle] Dissolving out by the action of a percolating liquid.

• Appears in modules:

• The Phosphorus Cycle

[person - calculus, statistics] French mathematician, naturalist, and biologist, born in Montbard, Côte-d'Or (1707-1788). In 1727, Leclerc discovered the binomial theorem. In the 1730s, 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.

• Appears in modules:

• Adaptation

[person] Danish physicist born in Osterbro by the Lakes (1888-1993). In 1925, Lehmann became interested in seismology while working as assistant to Professor N.E. Norlund. Three years later, she was appointed chief of the seismological department at the Royal Geodetic Institute. Because Denmark is seismically stable, Lehmann focused her research on small 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 in 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.

• Appears in modules:

• Earth Structure

[adjective - stellar and galactic astronomy, atmospheric science, rocks & minerals, weather & climate] Shaped like a lens, of or related to a lens; often referring to clouds, galaxies, rock bodies, or small features within rocks.

[noun - cells, medicine] Nearly colorless cells of the immune system that circulate mainly in the blood and lymph. Leukocytes participate in the immune system's reactions to invading microorganisms or foreign particles.

[person - biomolecules, genetics & inheritance] (February 25, 1869 - September 6, 1940) A Russian-American biochemist who studied the structure and function of nucleic acids, differentiated DNA and RNA (the two types of nucleic acid), and discovered that DNA consists of adenine, guanine, thymine, cytosine, deoxyribose, and a phosphate group. Levene is remembered for his "tetranucleotide hypothesis," which he formulated around 1910 and which stated that DNA was composed of equal amounts of adenine, guanine, cytosine and thymine. Levene thought that DNA was too simple a molecule to carry genetic information, and favored the hypothesis that genetic material was stored instead in protein. Despite his misconceptions, his work contributed greatly to the eventual discovery of the importance of DNA.

• Appears in modules:

• DNA II

[person - atoms & subatomic particles, physical & chemical properties] 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.

[noun - anatomy & physiology, evolution & adaptation, organisms] Fungi that live symbiotically with photosynthetic algae or bacteria.

• Appears in modules:

• Cellular Organelles I
• Exponential Equations in Science I

[noun - energy, light & optics] 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.

• Appears in modules:

• Atomic Theory I
• Atomic Theory II
• Atomic Theory III
• Atomic Theory IV
• Biodiversity I
• Carbohydrates
• Cell Division I
• Cellular Organelles I
• Charles Darwin I
• Chemical Reactions
• Composition of Earth's Atmosphere
• Data Analysis and Interpretation
• Diffusion I
• Discovery and Structure of Cells
• DNA I
• Ellen Ochoa
• Energy
• Experimentation in Scientific Research
• Factors that Control Earth's Temperature
• Factors that Control Regional Climate
• Gravity
• History of Earth's Atmosphere I
• History of Earth's Atmosphere II
• Introduction to Descriptive Statistics
• Kevin Arrigo
• Kinetic-Molecular Theory
• Light and Electromagnetism
• Light I
• Luis Walter Alvarez
• Measurement
• Membranes I
• Mendel and Inheritance
• Meselson and Stahl
• Modeling in Scientific Research
• Nuclear Chemistry
• Photosynthesis I
• Properties of Minerals
• Properties of Solids
• Scientific Ethics
• Scientists and the Scientific Community
• States of Matter
• Statistics in Science
• The Carbon Cycle
• The Nature of Scientific Knowledge
• The Phosphorus Cycle
• The Practice of Science
• The Process of Science
• The Silicate Minerals
• Understanding Scientific Journals and Articles
• Using Graphs and Visual Data in Science
• Utilizing the Scientific Literature
• Wave Mathematics

[noun - rocks & minerals] A sedimentary rock composed mainly of calcite (CaCO₃). Limestone forms through chemical precipitation in warm, shallow seas, and often contains marine fossils.

• Appears in modules:

• Origins of Plate Tectonic Theory
• The Carbon Cycle

[noun - evolution & adaptation, nutrition, organisms, energy, matter, organic & biochemistry, hydrology & fresh water, oceanography, biodiversity & ecological relationships, energy resources, human impacts on the environment, natural resources, nutrient cycles, organisms] The essential resource an organism needs for life that is in shortest supply in their environment. In environmental science, this usually means the resource (e.g., food supply, water supply, air to breathe) that is limiting the growth of an organism or population within a given ecosystem. For example, the number of fish that can survive in an aquarium depends on the amount of food, dissolved oxygen, and space available. If there is enough space and oxygen, but not enough food, the fish population will decrease. The individual organisms will only be able to survive as long as their basic needs for life are met. The factor that is in least supply is limiting the growth of the organism and/or population.

[noun - anatomy & physiology, biomolecules, nutrition, organisms, compounds, elements, energy, organic & biochemistry, physical & chemical properties, energy resources, natural resources, nutrient cycles, organisms] An essential nutrient an organism needs for life that is in the shortest supply in their environment. For example, a tomato plant requires specific amounts of nitrogen, phosphorus, and potassium to grow and produce fruit. A soil sample from a garden shows adequate amounts of nitrogen and phosphorus, but a very low amount of potassium. Potassium is the limiting nutrient in this instance because the tomato plants do not have enough potassium to perform the cellular processes needed for growth and reproduction. Growth will continue if more potassium is added to the soil. The nutrient in least supply is limiting the organism’s ability to grow and reproduce.

• Appears in modules:

• The Phosphorus Cycle

[noun - chemical reactions] The reactant which, according to the mole ratio of the chemical equation, will be used up first and determines the amount of product created in the reaction.

[noun - hydrology & fresh water, biodiversity & ecological relationships, bioregions, biomes & ecosystems, natural resources, nutrient cycles] A scientist whose focus is the study of inland water bodies (e.g., lakes, rivers, streams) and their surrounding environment. This includes the interactions between the plants and animals in and around the water bodies, as well as the effect of geology (e.g., topography, soils) and weather. Limnology includes the study of inland salt-water bodies, like the Lochs of Scotland and Great Salt Lake in Utah, as well as freshwater bodies.

• Appears in modules:

• The Phosphorus Cycle

[noun - energy, light & optics] 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.

• Appears in modules:

• Atomic Theory II
• Using Graphs and Visual Data in Science

[person - matter] An English Jesuit scientist (1595 – 1675). Line championed Aristotle’s idea that “nature abhors a vacuum” in the 17th century, and therefore proposed the idea of “funiculus,” a substance that materializes to extinguish a vacuum. The existence of funiculus was disproven by Robert Boyle in the mid-17th century.

• Appears in modules:

• Properties of Gases

[noun - organisms, taxonomy & systematics] In organisms, lineage is the line of descent from an ancestor.

• Appears in modules:

• Cellular Organelles I
• Charles Darwin III
• Introduction to Paleoanthropology
• Y-Chromsome and Mitochondrial DNA Haplotypes

[adjective - equations] An equation that makes a straight line when plotted on a graph.

• Appears in modules:

• Charles Darwin III
• Chemical Bonding
• Data Analysis and Interpretation
• DNA II
• DNA III
• Exponential Equations in Science I
• Introduction to Inferential Statistics
• Kinetic-Molecular Theory
• Linear Equations in Science
• Photosynthesis I
• Properties of Minerals
• The Nature of Scientific Knowledge
• The Practice of Science
• The Scientific Method

[forces, matter] Also called momentum, it is the product of an object’s mass and velocity, represented by a vector quantity. Units are often in kg · m/s.

[noun - statistics] A statistical method for modeling the relationship between a dependent variable and one or more independent variables. The stronger the relationship between the dependent and independent variables, the closer they will fall on a straight line when plotted against one another. Also see correlation.

• Appears in modules:

• Introduction to Inferential Statistics

[noun - taxonomy & systematics] The seven major categories of biological classification based on Linnaeus’ system: Kingdom, Phylum, Class, Order, Family, Genus, and Species.

[person - taxonomy & systematics] (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.

• Appears in modules:

• Taxonomy I
• Theories, Hypotheses, and Laws

[person - matter, physical & chemical properties] An English Jesuit scientist, born Francis Line (1595 – 1675). Linus championed Aristotle’s idea that “nature abhors a vacuum” in the 17th century, and therefore proposed the idea of “funiculus,” a substance that materializes to extinguish a vacuum. The existence of funiculus was disproven by Robert Boyle in the mid-17th century.

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

• Appears in modules:

• Absorption, Distribution, and Storage of Chemicals
• DNA I
• DNA III
• Energy Metabolism I
• Fats and Proteins
• Membranes I
• Membranes II

[noun - matter, physical & chemical properties, matter] The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience some type of intermolecular interaction. Unlike solids, liquids do not have fixed shapes and take the shape of their container (as do gases). Compare with gas and solid.

• Appears in modules:

• Acids and Bases I
• Blood Biology I
• Carbon Chemistry
• Defining Minerals
• Density
• Diffusion I
• DNA I
• DNA III
• Early Ideas about Matter
• Earth Structure
• Experimentation in Scientific Research
• Factors that Control Earth's Temperature
• Franklin Chang Díaz
• History of Earth's Atmosphere I
• Kinetic-Molecular Theory
• Lipids
• Luis Walter Alvarez
• Measurement
• Modeling in Scientific Research
• Origins of Life I
• Photosynthesis I
• Properties of Liquids
• Properties of Solids
• Solutions, Solubility, and Colligative Properties
• States of Matter
• Temperature
• The Hydrologic Cycle
• The Mole and Atomic Mass
• Water

[noun - landforms & geologic formations, seismology & plate tectonics] The rigid upper layer of Earth consisting of the crust and the upper mantle. 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.

• Appears in modules:

• Earth Structure
• The Phosphorus Cycle

[noun] an official record of events during a voyage at sea or other journey

[noun - atoms & subatomic particles, matter, forces, matter] An intermolecular force between temporary dipoles, where opposite charges created by temporary uneven distribution of electrons interact favorably.

• Appears in modules:

• Properties of Liquids
• Solutions, Solubility, and Colligative Properties

[organization - atoms & subatomic particles, chemical reactions] One of 17 national laboratories overseen by the US Department of Energy. LANL is located in Los Alamos, New Mexico, and was established in 1943 as a center for the design and development of the atomic bomb. Today, the focus of research at LANL is national security and nuclear deterrence.

• Appears in modules:

• Scientific Institutions and Societies

[person - energy, light & optics, thermodynamics] 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.

[person - atmospheric science, weather & climate, human impacts on the environment, weather & climate] British chemist, born in Letchworth Garden City (1919-). He developed the Gaia Hypothesis, which proposes that the biosphere and all physical components of Earth are coupled together in a complexly interacting system. The hypothesis is frequently paraphrased as describing 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.

• Appears in modules:

• The Practice of Science

[noun - planetary science, solar and lunar processes] A celestial event occurring when the moon passes through some portion of Earth's shadow. This only occurs when the sun, Earth, and moon are aligned so that Earth is between the sun and moon.

• Appears in modules:

• Description in Scientific Research
• The Nature of Scientific Knowledge
• Utilizing the Scientific Literature

[noun - rocks & minerals] The way an object reflects light; sheen, gloss.

• Appears in modules:

• Properties of Minerals

[person - landforms & geologic formations, seismology & plate tectonics] 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 our module The Rock Cycle.

• Appears in modules:

• Charles Darwin II
• The Rock Cycle

[noun - cells] Second most abundant type of white blood cell in the blood of vertebrates.

• Appears in modules:

• César Milstein