SCIENCE STAAR VIPs
(Very Important Phrases)
- A=P=E Atomic Number = protons = electrons
- M-A=N Atomic Mass – Atomic Number=Neutrons
- Kinetic Energy - the energy of movement (highest KE @ lowest point)
- Potential Energy - stored energy due to an object’s position (highest PE @ highest point)
- DRY – MIX (Dependent Responding Y-axis – Manipulated Independent X-axis)
- A PROTON identifies an ELEMENT!!! (= to Atomic #)
- Plate Tectonic Boundaries
- Convergent – collide and can form volcanic mountains, island arcs and trenches
- Divergent – pull apart and can form new sea floor such as Mid Ocean Ridge
- Transform – slide past each other and can cause earthquakes
- Weathering – breaking down of rock (wind, water, roots, gravity, human activity)
- Erosion – moving of that material by wind, water, gravity
- Waxing moon – during lunar cycle when moon is getting more and more visible
- Waning moon – during lunar cycle when visible part of moor is getting smaller and smaller (less visible)
- During the process of photosynthesis the products plants produce are glucose and oxygen
- Reactants are on the left of a chemical equation; Products are on the right
- Forces can be BALANCED but MOVING if all other forces cancel each other out (constant speed)
- Newton’s Laws of Motion
- Inertia – obj will travel in straight line @ constant speed
- Force/Acceleration – F=ma; therefore, a=F/m
- Action/Reaction – For every action there is an = & opp reaction
8th GRADE SCIENCE STAAR REVIEW
Topographic Maps
Contour Lines - lines connect points of equal elevation (heightabove sea level); the closerthe lines are spaced, the steeper(greater) the change inelevation.
Contour Interval: distance betweencontour lines.
Living Systems and theEnvironment
ORGANISMS AND THEIR NEEDS
BIODIVERSITY: Diverse life/many different organisms are very good!!!
Organism: a living thing (plant or animal)
Needs: organism’s requirements to survive (food, water, shelter, mate); organisms depend on other organisms and their habitat to meet their needs (birds build nests using twigs or trees)
Competition: struggle for limited amount of resources (food, water, oxygen) that an organism needs or it will die (plants in a forest compete for sunlight and water)
Ecosystem: the mixture of all living and nonliving things and conditions in a particular area. Biotic-living and abiotic-nonliving; Example: animals, plants, sunlight, and water
Environment: surrounding conditions where different environments contain different species of plants and animals
Species: organisms with similar characteristics, living in the same area and reproduce with each other (brown bears) to produce more offspring; may naturally (native) live or not naturally (invasive) live in an ecosystem.
Population: organisms of a particular species that live in the same area and breed with each other (all the brown bears in the northern forests)
Community: all the populations that live and interact in a particular area (all plants and animals in a northern forest)
Habitat: area an organism lives in and gets its needs met in (lake)
Niche: the role a species plays in an ecosystem (chipmunks eat nuts and berries from trees in forest)
Ecological Succession: gradual replacement of plants and animals over time as the results of an environmental change (burned down forest will be replaced with grasses, then shrubs, then trees)PRIMARY (from rock) & SECONDARY (forest fire, volcanic eruption – seeds & roots already there)
ROLES OF ORGANISMS
Animal Source of food Example
Herbivore plantshorse
Carnivoreanimals (meat)lion
Omnivoreplants & animalsraccoon
Term Role Example
Predatorhunts/eats otherstiger
Preyhunted as foodsquirrel
Scavengergets food from dead animalsvulture
Producermakes own foodplant
Consumergets food from other organismanimal
Decomposergets food from dead organismfungi
or waste of organisms
FOOD CHAINS/Webs
Food Chain: describes how energy is passed from one organism to another; energy begins with the sun and is passed or producers and then to consumers; energy moves in the direction of the arrows from one organism to another.
Food Web: picture that illustrates the many food chains in an ecosystem; arrows show the direction the energy moves(insect gets energy from grass, bird gets energy by eating insect)
SURVIVAL OF POPULATIONS
Carrying Capacity: maximum population that can live in an area over a long period of time (controlled by limiting factors)
Limiting Factors: factors that control a population’s size
EXAMPLE: food, water, shelter, living area
Environmental Changes: changes in the environment that can affect the survival of an organism or species
Example: If a river floods, fish and nutrients are carried down stream and the food supply for local bears will decrease. The bear population will decrease unless they find a different food source.
Extinction: when a species cannot get what it needs, it will die out (example: dinosaurs, certain whale species, and trilobites)
Impacts on Organisms’ Population: effect on a population caused by changes in the amount of food, water, predators or possible disease affecting it.
Human Impact: humans have changed ecosystems in bad ways (such as through air/water pollution) or in good ways (such as reforestation and conservation); impacts can be short term or long term
PHOTOSYNTHESIS
During photosynthesis plants transform the Sun’s energy in the form of light, into chemical energy in the form of glucose (sugar). Animals eat plants or other animals that have eaten plants and use the energy from the glucose.
Carbon Dioxide-Oxygen Cycle: during photosynthesis plants produce oxygen that animals need for respiration; during respiration animals produce the carbon dioxide that plants need for photosynthesis.
Carbon dioxide + water produces glucose + oxygen
Structure and Properties of Matter
PROPERTIES
Matter: anything that has mass and takes up space. All things living and nonliving are made of matter. These things are classified by properties or characteristics that can include:
ATOMS
Atoms are extremely small particles of matter (the building blocks). The nucleus is the center part of the atom that contains most of the atom’s mass. An atom is made up of three main parts.
Atomic PartLocationCharge
ProtonNucleuspositive (+)
NeutronNucleusneutral (no charge)
ElectronElectron Cloudnegative (-)
CLASSIFICATION OF MATTER
Element: substance made of only one type of atom
Examples: hydrogen, carbon, oxygen, silicon
Molecule: substances made of more than one atom
Examples: water (H2O) two hydrogen atoms and one oxygen atom; ozone (O3) three oxygen atoms
Compound: substance made of two or more elements
Example: salt (NaCl) one sodium atom and one chlorine atom
Mixture: two or more substances mixed together but maintaining their own properties and not making a new substance. They can be separated.
Example: M&M’s, a salad, trail mix
Solution: mixtures that are blended together and their properties also become blended throughout. One substance dissolved into another substance.
Example: sugar dissolved into water; chocolate syrup dissolved into milk
PERIODIC TABLE
Chemical Symbol: letters used to represent an element. An element’s abbreviation. First letter capitalized & second letter lower case.
Example: O for oxygen, Si for Silicon, Na for Sodium
Chemical Formula: easy way to express information about what atoms make up a substance.
Example: H2SO4 formula for sulfuric acid
Subscript: number to the lower right of an element’s symbol that represents the number of atoms of that element. If there is NO subscript then there is automatically one atom of that element.
Example: H2SO4 indicates that there are 2 atoms of Hydrogen, one atom of Sulfur and four atoms of Oxygen
Periodic Table: chart that shows all the elements. arranged in rows according to increasing atomic number. Columns represent elements that are similar in characteristics. There are 18 columns or families of elements and 7 periods (rows).
Valence Electrons: determined by the number of electrons that an atom will lose or gain in forming a chemical compound.
METALS, NONMETALS AND METALLOIDS
Metalleft side of periodic table (except hydrogen)
Nonmetalright side of periodic table
Metalloidalong the zigzag line (stair step) (except Al)
Metals: shiny, can bend or be pulled, good conductors of electricity; many are solids at room temperature.
Nonmetals: dull, brittle, poor conductors of electricity; many are gases at room temperature.
Metalloids: They conduct electricity under some conditions.
CHEMICAL REACTIONS AND PHYSICAL CHANGES
Law of Conservation of Mass: states that matter cannot be created or destroyed in an ordinary chemical reaction. The mass of the reactants must equal the mass of the products.
Physical Change: change in size, shape, or state yet still the same substance.
Chemical Reaction: process where there are combinations or divisions of substances that result in a new product or new substance.
Example: N2 + O2 2 NO (Nitrous Oxide)
Sea Breeze: daytime wind from ocean to land (high to low pressure)
Land Breeze: nighttime wind from land to ocean (low pressure to high)
Motion, Forces, and Energy
ENERGY
Energy: the ability to do work (to more or change matter)
Potential Energy: stored energy (energy of position)
Example: A roller coaster at the top of the hill has more potential energy than at the bottom.
Kinetic Energy: energy of motion
Kinetic vs. Potential Energy
ENERGY TRANSORMATION
Energy can be changed (transformed) from one type of energy to another. Energy is transformed to meet needs.
Examples:
- Chemical energy from gasoline is converted to mechanical energy in order to drive a car through combustion
- Chemical energy from batteries is converted to light energy in a flashlight.
- Electrical energy is converted to thermal energy with you use a toaster.
- Mechanical energy is converted to sound energy when you strike the keys on a piano.
FORCE
Force: a push or pull; force is needed to start or stop a motion. The force depends on the mass of an object
Force = mass x acceleration (unit Newtons N)
Example: The force applied to a soccer ball when it is kicked will make it roll in a certain direction.
Balanced Force: when the forces acting on an object are perfectly balanced against one another; does not result in change in speed or direction of an object.CAN BE BALANCED but MOVING!
Unbalanced Force: Opposing forces are NOT equal and can result in a change of speed and/or direction
Resistance Force: force, like friction that opposes motion
Gravity: the force that pulls objects in the universe towards one another. Gravity is not the same throughout the universe; such as Earth has a greater gravitational force than the Moon due to mass.
Weight: a measurement of the force of gravity on an object as a result of the acceleration of gravity (9.8 m/s2).
Weight = mass x gravity
Newton’s Laws of Motion
1st Law: 2nd Law:
3rd Law:
MOTION
Motion: change in the position of an object over a certain amount of time
Speed: rate at which object moves
Speed = distance ÷ time
Velocity: describes speed in a given direction
Acceleration: rate at which velocity changes
WORK AND SIMPLE MACHINES
Work: force acting over a distance
Work (J) = Force (N) x distance (m)
Work is ONLY being done when you MOVE an object a specific DISTANCE when you apply a FORCE to it! W=F x d
Earth and Space Systems
THE UNIVERSE
Universe: consists of all matter, energy and space
Galaxy: a group of stars and other particles connected by gravity
Stars: enormous balls of superheated gases. Radiates energy through nuclear fusion. Color spectrum depends on the temperature of the star and brightness depends on its temperature, size and distance from Earth.
H-R Diagram: Major grouping of stars according to their temperature
& luminosity
Nebula: huge cloud of gas and dust; believed to be where stars first form.
Comets: object made of ice, rocks and dust that circle the Sun in long elliptical orbits.
Planets: round objects that revolve around our Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus Neptune
Sun: medium sized, main sequence star that is the center of our solar system. Provides most of Earth’s energy.
Moon: Round object that revolves around the Earth or other planets in a circular path. A natural satellite.
Tides: daily movement of the Earth’s ocean surfaces due to the gravitational pull of the moon (rise and fall).
Spring Tide: largest difference between low & high tides
Neap Tide: smallest difference between low & high tides
Lunar Phases: stages the moon goes through as it revolves around the Earth each month.
Seasons: divisions of the year caused by the tilt of the Earth on its axis, combined with its revolution around the Sun
Length of Daylight: dependent on the distance north or south of the equator (latitude) and the season (longer daylight hours during summer.. less during winter)
CycleTime
Earth’s revolution around Sun365.25 days (one year)
Moon’s revolution around Earth29.5 days (one month)
Earth’s rotation on axis24 hours (one day)
PLATE TECTONICS
Theory that Earth’s lithospheric plates are broken into pieces that move slowly due to convection currents.
BoundaryPlate MovementResults
Convergentplates collidemountains, volcanoes,
ocean trenches
Divergentplates pull apartrift valleys, sea floor
spreading
Transformslide pastfaults, earthquakes
COMMON VOCABULARY TERMS FOUND ON THE STAAR TEST
Ability – to be able to do something; to act. Example: Humans have the ability to stop global warming if they stop putting carbon dioxide into the atmosphere.
Advantage – a benefit or a good result. Example: Changing lab partners will be an advantage for you.
Alternative – a chance to choose between two different things. Example: Solar energy is an alternative to using fossil fuels.
Aquifer – layer of rock or sand below the surface of the Earth that holds water (runoff)
Conclusion – the final part of something or the final results. Example: After the experiment the students came to the conclusion that it did not work.
Consumed – to be used up. Example: The United States consumed large amounts of fossil fuel last year.
Debris – material that is broken into pieces. Example: The debris from the explosion landed over 500 meters away.
Difference–the amount by which one number or quantity differs from another (often shown as subtraction). Example: What is the difference in the size of the two fish that were caught?
Function – the proper or natural use of anything. A special duty or action required. Example: What is the function of the heart in the circulatory system?
Generated – made or created. Example: The power plant generated electricity by using solar energy.
Impact – the effect an action will have on something; Example: What is the environmental impact of carbon dioxide in the atmosphere?
Initial – existing at the beginning or first. Example: The initial formation of our solar system began about 5 billion years ago.
Intense – extremely high, very large amount. Example: The intense amount of heat from the fire affected the wildlife in the area.
Land Subsidence – a weak area in the Earth’s crust that can collapse inward or sink. Example: When water is pumped out of the ground, land subsidence can occur and the ground level will sink.
Limitation – limiting factor (drawback or problem); Example: What is the limitation in this experiment?
Maintain – to go with; continue; to keep in operation or proper condition. Example: Force had to be applied to the object in order to maintain its movement.
Pesticide – chemical used to control or kill pests such as insects, rodents, plants or fungi. Example: The farmer sprayed pesticide on his crops in order to be able to increase crop production.
Promotes – to contribute to the growth, success or development of something. Example: What material will promote the growth of the corn plant?
Raising – going up or increasing in value. Example: Is raising the temperature going to affect the outcome of this experiment?
Reasonable – being within the boundary of reason (a rational answer). Example: The student gave a reasonable answer to the teacher’s question.
Reducing or Decreasing – lowering the amount (going down). Example: Will reducing the CO2 in the atmosphere help slow down the greenhouse effect?
Represents – to present a likeness or image; to serve as a symbol, sign or expression of an object. Example: Which of the following models best represents the solar system?
Variety – number of different things in a group; some varying from the others of the same kind. Example: There is a great variety of wildflowers growing along the side of the highway.
Vaporized – turned into vapor or smaller pieces. Example: The flash from the explosion vaporized all life on Earth.
Weakened – to make or become weak or less strong. Example: Not collecting enough data during the experiment weakened the final results.