| A | B |
|---|
| Adaptation | a change by which an organism becomes better suited to its environment |
| Air | the invisible gaseous substance surrounding the earth, a mixture mainly of oxygen and nitrogen |
| Air mass | a body of air extending hundreds or thousands of miles horizontally, that maintains nearly uniform conditions of temperature and humidity at any given level |
| Air pressure | the pressure exerted by the atmosphere |
| Amino Acid | the building blocks of proteins |
| Amplitude | the maximum extent of a vibration or oscillation from the point of equilibrium |
| Anatomy | the science of the shape and structure of organisms and their parts |
| Asexual reproduction | reproduction without the fusion of gametes (egg and sperm) |
| Astronomy | the science of celestial objects, space and the physical universe |
| Atmosphere | the envelope of gases surrounding the earth or another planet |
| Atom | the smallest particle of an element, consisting of a positive nucleus surrounded by negatively charged electrons |
| Axis | an imaginary line through a body, about which it rotates |
| Binary fission | a method of asexual reproduction, involves the spitting of a parent cell into approximately equal parts |
| Biodiversity | the variability among living organisms on the earth, including the variability within and between species and within and between ecosystems. |
| Biology | the scientific study of living organisms |
| Biosphere | the part of the earth and its atmosphere in which living organisms exist or that is capable of supporting life |
| Boiling point | the temperature at which a liquid boils at a fixed pressure, especially under standard atmospheric conditions |
| Botany | the scientific study of plants |
| Carbohydrate | any of a group of organic compounds that includes sugars, starches, celluloses, and guns and serves as a major energy source in the diet of animals. Contain only hydrogen, carbon and oxygen |
| Carcinogen | a cancer-causing substance |
| Cell | the smallest structural unit of an organism |
| Cell division | the process in reproduction and growth by which a cell divides to form daughter cells |
| Cellular respiration | the process by which living cells break down food molecules to release energy and carbon dioxide. |
| Chemistry | the scientific study of matter and its interactions |
| Chloroplast | a structure in green plant cells and some algae which contains chlorophyll and in which photosynthesis takes place |
| Chromosome | a thread-like structure found in the nuclei of most living cells, carrying genetic information I in the form of genes |
| Circuit | a closed path followed by an electric current |
| Classification | the systematic grouping of organisms into categories based on evolutionary or structural relationships between them |
| Climate | prevailing meteorological conditions in a particular region, including temperature, precipitation, and wind |
| Cloud | a visible body of very fine water droplets or ice particles suspended in the atmosphere at altitudes ranging up to several miles above sea level. |
| Cohesion | the intermolecular attraction by which the elements of a body are held together |
| Communicable Disease | a disease that can be transferred from one person to another |
| Community | a group of interdependent plants or animals growing or living together or occupying a specified habitat |
| Composition | the combining of distance parts or elements to form a whole |
| Compound | a pure, homogeneous substance consisting of atoms or groups of atoms combined in a definite ratio, that cannot be separated by physical means |
| Conclusion | a judgment or decision reached by reasoning |
| Condensation | the process by which a gas changes to a liquid |
| Heat of Condensation | heat liberated by a unit mass of gas at its boiling point as it condenses into a liquid |
| Conduction | the transmission of something through a medium, especially of electric charge or heat through a conducting medium. |
| Conductivity | the ability to conduct or transmit heat, electricity or sound |
| Conservation of energy | a principle stating that the total energy of a system remains constant regardless of changes within the system |
| Conservation of mass | a principle stating that the total mass of a system is unchanged by interaction of its parts |
| Conservation of matter | a principle that matter cannot be created or destroyed in an isolated system |
| Controlled experiment | an experiment that isolates the effect of one variable on a system by holding all variables constant except the one under observation |
| Convection | heat transfer in a gas or liquid by the circulation of currents from one region to another |
| Coriolis effect | result of an apparent force that as a result of the earth's rotation deflects moving objects to the right in the northern hemisphere and to the left in the southern hemisphere |
| Data | factual information used as a basis for reasoning, discussion or calculation |
| Decomposition | breakdown or decay of material |
| Density | the mass of a substance per unit volume |
| DNA | Deoxyribonucleic acid - the carrier of genetic information - present in nearly all living organisms |
| Earthquake | a sudden movement of the earth's crust caused by the release of stress accumulated within the earth's crust |
| Eclipse | the partial or complete obscuring, relative to an observer, of one celestial body by another |
| Ecology | the branch of biology concerned with the relations of organisms to one another and to their physical surroundings |
| Ecosystem | a biological community of interacting organisms and their physical environment |
| Electricity | a form of energy resulting from the existence of charged particles, either statically as an accumulation of charge, or dynamically as a current |
| Electromagnetic radiation | a kind of radiation including visible light, radio waves, gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously |
| Electron | a negatively charged subatomic particle found in all atoms |
| Element | a substance composed of atoms having an identical number of protons in each nuclei, that cannot be reduced to simpler substances by normal chemical means. |
| Elevation | height above a given level, especially sea level |
| Energy | the capacity of a system to do work |
| Environment | the complex of physical, chemical, and biotic factors that act upon an organism or an ecological community and determine its form and survival |
| Equilibrium | the state of a chemical reaction in which its forward and reverse reactions occur at equal rates so that the concentration of the reactants and products does not change with time |
| Erosion | wearing away of the earth's surface by natural processes including weathering, dissolution, abrasion, corrosion and transportation |
| Evaporation | process by which the surface liquid changes into a gas |
| Experiment | a test under controlled conditions to test a hypothesis |
| Food Chain | a succession of organisms in an ecological community that constitutes a continuation of food energy from one organism to another as each usually consumes a lower member and is preyed upon by a higher member |
| Food Pyramid | a graphic representation of the structure of a food chain, depicted as a pyramid having a broad base formed by producers and tapering to a point formed by end consumers. |
| Food Web | a complex of interrelated food chains in an ecological community |
| Force | a push or a pull on an object |
| Fossil | a remnant or trace of an organism of a past geologic age, such as a skeleton or leaf imprint, embedded and preserved in the earth's crust |
| Fossil fuel | a hydrocarbon deposit, such as petroleum, coal, or natural gas, derived from living matter of a previous geologic time and used for fuel |
| Frequency | the number of complete cycles of a periodic process occurring per unit of time |
| Front | the interface between air masses of different temperatures or densities |
| Galaxy | a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction |
| Gas | the state of matter characterized by having no definite shape or volume |
| Genetics | the branch of biology that deals with heredity |
| Geologic time | the period of time covering the physical formation and development of Earth, especially the period prior to human history |
| Geology | the scientific study of the origin, history, and structure of the earth |
| Geosphere | the solid part of the earth consisting of the crust and outer mantle |
| Glacier | a huge mass of ice slowly flowing over a land mass, formed from compacted snow in an area where snow accumulation exceeds melting and sublimation |
| Gravity | the force that attracts a body towards the center of the earth, or towards any other physical body having mass |
| Greenhouse effect | the phenomenon whereby the earth's atmosphere traps solar radiation and absorbs heat radiated back from the earth's surface - caused by carbon dioxide, water vapor and methane in the atmosphere |
| Greenhouse gas | a gas, such as carbon dioxide, that contributes to the greenhouse effect by absorbing infrared radiation |
| Groundwater | water beneath the earth's surface, often between saturated soil and rock, which supplies wells and springs |
| Habitat | the area or environment where an organism or ecological community normally lives |
| Heat | a form of energy associated with the motion of atoms or molecules and capable of being transmitted through solid and fluid material through conduction, through fluid material by convection, and through empty space by radiation |
| Heat of Condensation | heat liberated by a unit mass of gas at its boiling point as it condenses into a liquid |
| Homeostasis | the ability of an organism or cell to maintain internal equilibrium by adjusting its physiological processes |
| Humidity | the amount of water suspended in the air in tiny droplets |
| Hydrologic cycle | the cycle of evaporation and condensation that controls the distribution of earth's water |
| Hydrosphere | the watery layer of the earth's surface, including water vapor |
| Hypothesis | a tentative explanation for an observation, phenomenon, or scientific problem that can be tested by further investigation |
| Infrared | electromagnetic radiation having a wavelength just greater than that of red light, but less than that of microwaves, emitted particularly by heated objects. |
| Inquiry | a systematic search for the truth or facts about something |
| Invertebrate | an animal, such as an insect or mollusk, which lack a backbone or spinal column |
| Investigation | a detailed inquiry or systematic examination |
| Kinetic energy | energy which a body possesses by being in motion |
| Life cycle | the course of developmental changes in an organism from fertilization to mature adult |
| Light | electromagnetic radiation that can produce a visual sensation |
| Liquid | the state of matter in which the substance has no definite shape, but does have a definite volume |
| Lithosphere | the rigid outer part of the earth, consisting of the crust and upper mantle. |
| Macromolecule | a very large molecule, such as a polymer or protein, consisting of many smaller structural units linked together |
| Macroscopic | large enough to be examined by the unaided eye |
| Magnetism | the property displayed by magnets and produced by the motion of electric charges, which results in attraction or repulsion between objects |
| Mass | the quantity of matter which a body contains |
| Matter | physical substance that occupies space and has mass |
| Meiosis | the process of cell division in sexually reproducing organisms that reduces the number of chromosomes by half in the formation of egg and sperm cells |
| Melting point | the temperature at which a solid becomes a liquid |
| Meteorology | the science that deals with the phenomena of the atmosphere, especially weather and weather conditions |
| Microscopic | too small to be seen by the unaided eye, but large enough to be seen under a microscope |
| Mineral | a naturally occurring solid substance having a definite chemical composition and characteristic crystalline structure, color and hardness |
| Mitosis | a type of cell division in which daughter cells have the same number and kind of chromosomes as the parent nucleus |
| Mixture | two or more substances that are not chemically combined with each other and are capable of being separated by physical means |
| Molecule | the smallest particle of a substance that retains the chemical and physical properties of the substance and is composed of two or more atoms. |
| Moon | the natural satellite of the earth, orbiting every 28 days, shining reflected light from the sun down to earth |
| Moon phases | one of the cyclically recurring apparent forms of the moon |
| Motion | change in position of an object in relation to a reference point |
| Multicellular | having many cells |
| Mutation | a change in genetic structure which results in a variant form and may be transmitted to future generations |
| Natural resources | a material source of wealth, such as timber, fresh water, or mineral deposit that occurs in a natural state and has economic value. |
| Natural selection | the process in nature by which only the organisms best adapted to their environment tent to survive and transmit their genetic characteristics in increasing numbers to succeeding generations while those less adapted tend to be eliminated. |
| Neutron | a subatomic particle of about same mass as a proton but without an electric charge |
| Niche | the function or position of an organism or population within an ecological community |
| Nonrenewable resource | relating to an energy source, such as oil or natural gas, or a natural resource, such as a metallic ore, that is not replaceable after it has been used |
| Observation | the act of making and recording a measurement |
| Oceanography | the branch of science concerned with the physical and biological properties of the sea |
| Orbit | the path of a celestial body or satellite as it revolves around another body |
| Organism | a living thing that has the ability to function independently |
| Organ | a differentiated part of an organism, such as an eye, wing, leaf, which performs a specific function |
| Pangaea | a hypothetical super-continent that included all the landmasses of the earth, broke up into continents that drifted apart over time |
| Parasite | an organism that grows, feeds, and is sheltered on or in a different organism while contributing nothing to the survival of its host |
| Periodic table | a table of the chemical elements arranged in order of atomic number |
| pH | a measure of the acidity or alkalinity of a solution, numbered 0-14, with 7 being neutral. |
| Photosynthesis | the process in green plants and certain other organisms by which carbohydrates are synthesized from carbon dioxide and water using light as and energy source, releasing oxygen as a byproduct. |
| Physical change | a change from one state to another without a change in chemical composition |
| Physics | the science of matter and energy an on interactions between the two |
| Physiology | the branch of biology concerned with the normal functions of living organisms and their parts |
| Planet | a non-luminous celestial body larger than an asteroid or comet, illuminated by light from a star, such as the sun, around which it revolves. |
| Plasma | a phase of matter distinct from solids, liquids, and gases |
| Plate tectonics | a theory that explains the global distribution of geological phenomena such as seismicity, volcanism, continental drift, and mountain building in terms of the formation, destruction, movement, and interaction of the earth's lithosperic plates |
| Plateau | an elevated, comparatively level expanse of land |
| Polarity | the state of having poles or opposites |
| Pollination | transfer of pollen from the anther to the stigma of a plant |
| Population | all the organisms that constitute a specific group or occur in a specified habitat |
| Potential energy | energy possessed by a body by virtue of its position or state |
| Precipitation | any form of water, such as rain, snow, sleet, or hail, which falls to the earth's surface |
| Pressure | force applied uniformly over a surface, measured as a force per unit of area |
| Prevailing wind | a wind from the predominant or most usual direction |
| Proton | a stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron |
| Radiation | energy emitted as electromagnetic waves or subatomic particles |
| Radiometric dating | a method of determining the age of objects or material using the decay rates of radioactive components such as potassium-argon |
| Renewable resource | any natural resource that can be replenished naturally with the passage of time |
| Replication | the process whereby DNA makes a copy of itself before cell division |
| Reproduction | the sexual or asexual process by which organisms generate new individuals of the same kind |
| RNA (Ribonucleic Acid) | a substance in living cells which carries instructions from DNA for controlling protein synthesis |
| Rock | any natural material with a distinctive composition of minerals |
| Rotation | the act of turning around a center or an axis |
| Salinity | the relative proportion of salt in a solution |
| Satellite | any celestial body orbiting around a planet or star |
| Science | the study of the structure and behavior of the physical and natural world through observation and experiment |
| Scientific law | a phenomenon of nature that has been proven to occur whenever certain conditions exist or are met |
| Scientific theory | a well-substantiated explanation of some aspect of the natural world |
| Season | on of the natural periods into which the year is divided by the equinoxes and solstices or atmospheric conditions |
| Sedimentary rock | rock that has formed from sediment deposited by water or wind |
| Sexual reproduction | reproduction by the fusion of two different sex cells |
| Soil | the top layer of the earth's surface, consisting of rock and mineral particles mixed with organic matter |
| Solar System | a system of plants or other bodies orbiting another star |
| Solid | the state in which a substance has shape, and a definite volume |
| Solubility | the condition of being soluble |
| Soluble | can be dissolved |
| Sound | vibrations transmitted that can be detected by human hearing organs |
| Space | the expanse in which the solar system, stars, and galaxies exist |
| Species | a fundamental category of taxonomic classification consisting of related organisms capable of interbreeding |
| Specific heat | the ratio of the amount of heat required to raise the temperature of a unit mass of a substance by on unit of temperature to the amount of heat required to raise the temperature of a similar mass of a reference material (water), by the same amount. |
| Spectroscope | an instrument for producing and observing spectra, the entire range of wavelengths of electromagnetic radiation |
| Speed | the rate or measure of the rate of motion |
| Star | a celestial body of hot gases that radiates energy derived from thermonuclear reactions in the interior |
| Storm | a violent disturbance of the atmosphere with strong winds and usually rain, thunder, lightning, or snow |
| Stratosphere | the atmospheric layer between the troposphere and the mesosphere |
| Substance | a particular kind of matter with uniform properties |
| Sun | the star around which the earth orbits |
| Symbiotic | a close, prolonged association between two organisms |
| Synthesis | formation of a compound from simpler compounds or elements |
| System | a group of interacting, interrelated, or interdependent elements forming a complex whole |
| Telescope | a scientific instrument designed to collect and record electromagnetic radiation from cosmic sources |
| Temperature | the measure of the average kinetic energy of the particles in a sample of matter, expressed in terms of units or degrees designated on a standard scale |
| Theory | a well-substantiated explanation of some aspect of the natural world |
| Thermal | relating to heat |
| Tide | the alternate rising and falling of the sea due to the attraction of the moon and sun |
| Tissue | any of the distinct types of materials of which animals or plants are made, consisting of specialized cells and their products |
| Troposphere | the lowest region of the atmosphere in which weather occurs |
| Ultraviolet | electromagnetic radiation having a wavelength just shorter than violet light, but longer than that of X-rays |
| Unicellular | consisting of a single cell |
| Universe | all matter and energy, including the earth, the galaxies, and the contents of intergalactic space, regarded as a whole |
| Velocity | the speed of something in a given direction |
| Vertebrate | animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium |
| Visible light | electromagnetic radiation that can produce a visual sensation |
| Volcano | an opening in the earth's crust through which molten lava, ash, and gases are ejected |
| Volcanic eruption | the sudden occurrence of a violent discharge of steam and volcanic material |
| Volume | the amount of 3-dimensional space occupied by and object |
| Wavelength | the distance between successive crests of a wave |
| Weather | the state of the atmosphere at a given time and place with respect to temperature, moisture, wind velocity, and barometric pressure |
| Weathering | any of the chemical or mechanical processes by which rocks exposed to the weather undergo changes in character and break down |
| Weight | the vertical force exerted by a mass as a result of gravity |
| White light | apparently colorless light containing all the wavelengths of the visible spectrum |
| Wind | moving air, especially a natural and perceptible movement of air parallel to or along the ground |
| X-ray | an electromagnetic wave of very short wavelength able to pass through many materials |
| Year | the time taken by earth to make one revolution around the sun |
| Zoology | the scientific study of the behavior, structure, physiology, classification and distribution of animals. |
