Science, Grades 6-8 – 119 Words

asexual reproduction

reproduction without the fusion of gametes


a small celestial body composed of rock and metal


the envelope of gases surrounding any celestial body

atmospheric pressure

the pressure exerted by the atmosphere


the smallest component of an element


a partiality preventing objective consideration of an issue

bulletin board system

a computer that is running software that allows users to leave messages and access information of general interest


capability to perform or produce


a compact disk that is used with a computer

celestial body

a natural object visible in the sky


the basic structural and functional unit of all organisms

cell division

the process in reproduction and growth by which a cell divides to form daughter cells

central processing unit

the part of a computer that does most of the data processing

chemical change

process determined by substances’ composition and structure

chemical compound

(chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight

chemical element

any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter

chemical energy

that part of the energy in a substance that can be released by a chemical reaction

chemical reaction

a process in which substances are changed into others

circulatory system

the organs and tissues involved in circulating blood and lymph through the body


the weather in some location averaged over a period of time

climate change

a change in the world’s climate


a small frozen mass that travels around the sun

conservation of energy

the fundamental principle of physics that the total energy of an isolated system is constant despite internal changes


a solid having a highly regular atomic structure

data processing

(computer science) a series of operations on data by a computer in order to retrieve or transform or classify information


the remains of something that has been destroyed


a decrease in rate of change


the kind of intellectual who converts messages from a code to plain text

digestive system

the system that makes food absorbable into the body


the act of taking something apart (as a piece of machinery)


the phenomenon when one celestial body obscures another


organisms interacting with their physical environment

egg cell

the female reproductive cell; the female gamete

electric current

a flow of electricity through a conductor

electrical energy

energy made available by the flow of electric charge through a conductor


the process in which output of a system is returned to input


the general appearance of a publication


the organization of information according to preset specifications (usually for computer processing)


what something is used for


an organism of the kingdom Fungi lacking chlorophyll and feeding on organic matter; ranging from unicellular or multicellular organisms to spore-bearing syncytia


a collection of star systems


Italian astronomer and mathematician who was the first to use a telescope to study the stars; demonstrated that different weights descend at the same rate; perfected the refracting telescope that enabled him to make many discoveries (1564-1642)


part of DNA controlling physical characteristics and growth

gravitational force

the force of attraction between all masses in the universe

heat energy

a form of energy that is transferred by a difference in temperature


metabolic equilibrium maintained by biological mechanisms


a person who invites guests to a social event


the watery layer of the earth’s surface


a tentative insight that is not yet verified or tested


a visual representation produced on a surface

igneous rock

rock formed by the solidification of molten magma

immune system

a system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response


the tendency of something to stay in rest or motion


the invasion of the body by pathogenic microorganisms

infrared radiation

electromagnetic radiation with wavelengths longer than visible light but shorter than radio waves

input device

a device that can be used to insert data into a computer or other computational device


a material with little electrical or thermal conductivity


a restricted computer network


any animal lacking a backbone or notochord

kinetic energy

the mechanical energy that a body has by virtue of motion

light year

the distance that light travels in a vacuum in 1 year


the part of the Earth consisting of the crust and mantle


the branch of philosophy that analyzes inference

Louis Pasteur

French chemist and biologist whose discovery that fermentation is caused by microorganisms resulted in the process of pasteurization (1822-1895)


fail to work properly


a sleeveless garment like a cloak but shorter

Marie Curie

French chemist who won two Nobel prizes

mechanical energy

energy in a mechanical form

metamorphic rock

rock altered by pressure and heat


small extraterrestrial body that hits the earth’s atmosphere


either not matched or unsuitably matched


the simplest structural unit of an element or compound


the relation between two organisms that benefit each other


the guidance of ships or airplanes from place to place

nervous system

the sensory and control apparatus consisting of a network of nerve cells


an open fabric woven together at regular intervals

nuclear reaction

(physics) a process that alters the energy or structure or composition of atomic nuclei


a structure in an animal specialized for some function


production of a certain amount

output device

electronic or electromechanical equipment connected to a computer and used to transfer data out of the computer in the form of text, images, sounds, or other media


the process by which a substance combines with oxygen


a colorless, odorless gas that is essential for respiration


an animal or plant that lives in or on a host

peer review

evaluate professionally a colleague’s work


the slow passage of a liquid through a filtering medium


synthesis of compounds in plants aided by radiant energy

Pierre Curie

French physicist; husband of Marie Curie (1859-1906)

plant tissue

the tissue of a plant


the act of preying by a predator who kills and eats the prey


animal hunted or caught for food

programming language

a language designed for programming computers


a wheel with a groove in which a rope can run


the act of spreading outward from a central source

reproductive system

organs and tissues involved in the production and maturation of gametes and in their union and subsequent development as offspring


a single complete act of breathing in and out

respiratory system

the system for taking in oxygen and giving off carbon dioxide; in terrestrial animals this is accomplished by breathing


the formation of reddish-brown ferric oxides on iron by low-temperature oxidation in the presence of water


any celestial body orbiting around a planet or star

scientific method

method of observation to test scientific hypotheses


the display of a motion picture

sedimentary rock

rock formed from consolidated clay deposits


the accumulation of matter deposited by some natural process

sexual reproduction

reproduction involving the union or fusion of a male and a female gamete

skeletal system

the hard structure (bones and cartilages) that provides a frame for the body of an animal

soil erosion

the washing away of soil by the flow of water


taxonomic group whose members can interbreed


a rate at which something happens


the male reproductive cell; the male gamete

sperm cell

the male reproductive cell; the male gamete


a screen-oriented interactive program enabling a user to lay out financial data on the screen

tape drive

a mechanism that transports magnetic tape across the read/write heads of a tape playback/recorder


a classification of organisms based on similarities


part of an organism consisting of an aggregate of cells

touch screen

a computer display that enables the user to interact with the computer by touching areas on the screen

universal solvent

hypothetical universal solvent once sought by alchemists


the address of a web page on the world wide web


animals having a bony or cartilaginous skeleton

visible light

(physics) electromagnetic radiation that can produce a visual sensation


a shared orientation leading to mutual understanding

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