124 terms

Middle School Science


Terms in this set (...)

abiotic factor
A non-living thing that has an effect on an organism in an ecosystem
To increase speed; to go faster
Changes in structures or behaviors that increase an organism's chance for survival in a particular environment
asexual reproduction
Process where a single cell can reproduce by itself
Thick blanket of gases surrounding the Earth EX: nitrogen, oxygen, and other trace gases
Tiny particles of matter; contain protons, neutrons, and electrons
balanced force
Occurs when the forces acting on an object are equal, so the object's speed and direction will remain the same
The way someone or something acts
biogeochemical cycle
Movement of elements among the solid Earth, oceans, atmosphere, and organisms EX: the same atoms of oxygen might move through the water of an ocean, be breathed in by a whale, become part of the atmosphere, move through a person's lungs, pass through a plant, become part of the soil
biotic factor
A living thing that has an effect on an organism in an ecosystem
An animal that eats meat
Basic unit of life found in all organisms
chemical property
A characteristic of a substance that determines how it will interact to form other substances EX: flammability, reactivity
Structure found in the nucleus that carries genetic information for an organism
Putting things into groups based on their properties or characteristics EX: elements are grouped by number of protons
Grouping objects or events by their properties
General weather conditions over many years
collecting data
Gathering and recording bits of information in an organized way
Sharing information with others through writing or speaking
Combination of two or more elements
The direct results of an action
constructive forces
Forces that deform and change the surface of the Earth EX: crust deformation, volcanic eruption, deposition of sediment
Organism that gets its food supply from other organisms or plants
convection current
Current of air moving or circulating within the Earth's system
Center of the Earth below the mantle; consists mostly of iron and has a dense liquid layer and a dense solid center sphere
Outermost layer of the Earth
crustal deformation
The bending, tilting, and breaking of the Earth's crust caused mainly by movement of the lithospheric plates
Time required for the Earth to make one rotation on its axis (24 hours)
To decrease speed; to go more slowly
Organism that breaks down and gets its food from dead organic matter
Measure of how much mass is contained in a given volume (density = mass/volume)
Movement of soil to another location caused by wind, water, or ice
destructive forces
Forces that wear away and change the surface of the Earth EX: weathering and erosion
detrimental interaction
An interaction that is harmful EX: effect of pollution by people on the earth's water or air
The number and variety of organisms in an area
Earth materials
Rocks, soil, water, and gases of the atmosphere
earth system
All the parts of the Earth: the atmosphere,oceans, living organisms, and solid earth together
Passing of one planetary body through the shadow of another EX: lunar and solar eclipses
All populations living together and the physical parts of the environment with which they interact
Negatively charged particle found in an atom orbiting the nucleus
Substance that cannot be broken down by chemical or physical changes; consists of only one kind of atom EX: iron, oxygen, uranium
Measure of the ability to do work EX: light energy, heat energy, electrical energy, and sound energy
energy conservation
Reducing the amount of energy used in order to preserve non-renewable resources
energy pyramid
Illustrates the feeding relationships between food chains and food webs
energy transfer
Changing energy from one form to another EX: potential to kinetic
The slow movement of weathered rock and soil from one place to another caused by water, wind, gravity, and glaciers
Proof or supporting data
Designing a way to test a hypothesis
Disappearance of a species from its geographical range
A fracture in the continuity of a rock formation caused by a shifting or dislodging of the earth's crust
food chain
Flow of energy from one organism to another in a community
food web
Connected or linked food chains in a community
Push or pull on an object; can be visible (friction, collision) or invisible (gravity, magnetism)
Imprinted remains of a plant or animal in sedimentary rock that give us clues to the Earth's past
Imprinted remains of a plant or animal in sedimentary rock that give us clues to the Earth's past
Rubbing of one object or surface against another that slows down the motion of the object and produces heat
The purpose or role of a body structure
Small part of an organism that determines a specific trait EX: eye color and hair color are determined by genes
geological time
The history of the Earth as determined by radioactive dating, rock sequences, and fossils
global climate
Average temperature, average precipitation, and average wind and other features of the Earth's atmosphere and the entire planet's surface
gravitational force
Invisible pull of gravity
Force of attraction that keeps the planets in orbit and our feet on the ground
Organism that eats only plants
Passing of characteristics or traits from one generation to another
Making predictions that can be tested in experiments
igneous rock
Rock formed from cooled and hardened magma
The tendency for an object at rest to remain at rest until acted upon by a force, and for an object in motion to maintain a constant speed in the same direction until acted upon by a force
Interpreting or explaining observations
inherited trait
Specific characteristic that is genetically determined and passed on from parent to child EX: detached or attached earlobes
Describes a response present from birth
A natural association or connection among things in an environment
kinetic energy
Energy produced by motion
Features that make up the Earth's surface EX: mountains, rivers, islands
learned trait
A trait or characteristic that one learns from someone else or practices EX: making eye contact when speaking to others
Thin outer shell of Earth consisting of the crust and the rigid upper mantle
lithospheric plates
Separate pieces of the lithosphere that move very slowly due to the motion of the mantle
Layer of rock below the Earth's crust
Determining the size or quantity of something
metamorphic rock
Rock formed from other rocks as a result of intense heat, pressure, or chemical processes
Process of cell division where the nucleus divides and two nuclei are formed
Two or more substances that are blended but can be separated using their physical qualities EX: a mixture of salt water can be separated by evaporating the water and leaving the salt; the physical quality of water that you would need to know would be its boiling point
Two or more atoms held together by an attractive force; smallest particle of a compound EX: molecule of water
moon's phases
Repeating pattern of the different moon shapes you see due to the moon's movement around the earth
Movement; change in position over time
nervous system
Network of nerve cells in animals that carries sensations in the body to the brain
Neutral particle of the atom found in the nucleus
Newton's Laws of Motion
Three laws that describe relationships between forces and motion: 1st law--inertia, 2nd law--acceleration, 3rd law--reciprocal action
Tiny, postively charged center of an atom that contains protons and neutrons; much more massive than electrons
Using the five senses (sight, sound, taste, touch, smell) to find out about objects or events
Body part with one or more special functions EX: heart, lungs, stomach
A living plant or animal
The process that plants and some other organisms use to convert light energy into usable food energy
physical change
A change in shape, color, size, or state that doesn't change the chemical composition EX: cutting wood into lumber, freezing water
physical property
Observable or measurable property in a substance EX: mass, density, boiling point, solubility
All individuals of a species that live together in a particular place like the desert or ocean
potential energy
Energy that is stored in an object that can be put into motion
An organism that hunts for food
Using background knowledge and prior observation to form an opinion of what will happen; not guessing
An organism that is hunted as food
Organism that makes its own food using energy from the sun EX: green plant
Positively charged particle found in the nucleus of an atom
Explain by using words to describe the qualities or characteristics of an object
Explain by using numbers to describe an object
reciprocal action
Law that maintains that for every action there is an equal and opposite reaction EX: stepping off a boat onto shore and as you step forward the boat moves backward
rock cycle
A series of processes in which rock changes from one type to another
Spinning of a planet on its axis
sedimentary rock
Rock formed from hardened deposits of sediment; may contain fossils
sexual reproduction
Process by which sex cells from two organisms join to form a new organism
solar system
The sun and the bodies that revolve around it EX: sun, Earth, moon, other planets
Amount of substance that will dissolve in a specific amount of another substance at a given temperature
Group of similar organisms that can mate and reproduce
How fast something is moving; distance travelled divided by elapsed time EX: miles per hour
Something that causes or encourages a response EX: shining a light (stimulus) might cause you to squint or close your eyes (response)
The arrangement of parts in an organism; structure and function of cell components are related
Something that has weight and takes up space, or the material of which something is made
Interacting or interrelated parts of a whole EX: Earth is a system of elements
Daily change in the level of the ocean surface caused by the gravitational pull of the moon on the Earth and its waters
A group of similar cells united to perform a specific function EX: muscle tissue
unbalanced force
Occurs when the forces acting on an object are not equal; one force is greater than the other which causes an object's speed or direction to change
water cycle
Continuous movement of water from the air to the Earth and back again EX: evaporation, precipitation, condensation
Slow process that causes rocks to crumble, crack, and break and changes a rock's physical form and chemical make up
Air moving from an area of high pressure to an area of low pressure
Time required for the Earth to make one revolution around the sun (365 days)