STAAR Study Guide
Scientific Process- How to Conduct Experiments
1.
2.
3.
4.
Every experiment begins with a question or problem
Form a hypothesis that answers the question – Ex: plants grow better in sunlight than darkness
Gather the materials needed to conduct the experiment Design and conduct an experiment that will test the hypothesis
a. Control the variable being tested – A variable is something you can change in an experiment. It is important to keep
everything the same except what you are testing. For example, if you are testing whether
plants grow best in sunlight or darkness, you will make sure both plants are the same, get the same amount of water, and are
fed the same food. The only thing you would change would be one plant in the sun and one in darkness.
b. Remember – repeating an experiment several times increases the reliability of results
5. Make observations and record data – use your 5 senses and lab materials to collect data
6. Use or make a model to help you understand something better – models have limitations (they are not always 100%
accurate). They help us see things that are too small or too big to see otherwise.
7. Form a conclusion that answers the question. An inference is a reasonable conclusion based on what you observe
Laboratory Equipment
Tool
Purpose
Hand lens
Magnifies objects - refraction
Tool
Ruler, tape
measure, meter
stick
Balance
Microscope
Magnifies objects- refraction
Telescope and
Binoculars
Camera
Make objects far away appear closer refraction
Makes large objects appear smallerrefraction
Used for heating up liquids
Scale
Have north and south poles, similar poles
repel, used to separate mixtures,
attraction, nickel, cobalt and steel
Makes pouring liquid easier
Thermometer
Hot Plate
Magnets
Funnel
Timer
Measure how much time has passed and
helps control the variable of time
Organisms and Environments
Compass
Computer
Sieve/strainer
Graduated Cylinder,
Beaker
Purpose
Measures distance, length, width,
height
Measures mass in grams (not
affected by gravity)
Measures weight (affected by
gravity)
Tells direction
Used to collect data and research
facts
Measures temperature
Water boils 100 C
Water freezes 0 C
Helps separate matter based on
size- smaller items get through
Measures volume of liquids using
liters or mLs.
Organism – any living thing (plant or animal)
Needs – all organisms need certain things to survive (food, water, shelter, space, oxygen). They depend on other organisms in their
habitat to help meet these needs (birds – trees) Birds use the tree to build a nest that protects their young from predators. The tree
depends on the bird to help disperse its seeds.
Competition – because there is a limited amount of resources to meet the needs of organisms, they compete for what they need in order to
survive or they will die. Trees planted close together will compete for water, nitrogen, and sunlight. They will grow
longer roots or make sure their seeds get dispersed far away so they can survive.
Ecosystem / Biome / Habitat – a combination of living (biotic – plants and animals) and non-living (a biotic – sun, soil, water, air) things
that exist in a certain area (deciduous forest, grassland, rainforest, desert, coral reef, tundra). The plants and animals in this area are
adapted to live there and interact with one another.
Species – organisms that have similar features and can breed ( bears, snakes)
Niche – the role a species plays in an ecosystem (bees pollinate flowers so they can reproduce)
Habitat – a home for plants animals and other organisms.
Extinct – when a species cannot meet their needs, they die out (dinosaur)
Endangered – when a species’ population decreases because it cannot meet its needs. It may become extinct over time.
Adaptation – a learned behavior (burrowing to avoid the desert heat) or inherited
physical feature (prickly spins on a cactus to limit water loss) that helps an organism survive
within an ecosystem. Ex: migration, hibernation, camouflage, mimicry, or metamorphosis (egg, larva, pupa, adult)
Purpose of Adaptation
Getting food
Protection
Reproduction
Water conservation
Getting oxygen
Examples
• Eagles have sharp beaks that they use to tear apart small animals.
• Female mosquitoes use their straw-like mouthparts to suck blood.
• Rosebuds have thorns that help protect them from plant-eating animals.
• When skunks are threatened, they can spray a bad-smelling liquid onto their enemies.
• The seeds of coconut palm trees float on water and can be carried from one island to another by
the ocean
• The shells around bird eggs help protect their young until they are ready to hatch.
• Lizards have scaly skin that prevents water loss.
• Some plants have small leaves to prevent water loss.
• Fish have gills that they use to take oxygen from the water in which they live.
• A dolphin breathes air through a single nostril on top of its head when it comes to the ocean’s
surface.
Traits and Behaviors
Traits – physical characteristics of an organism (color, height)
Inherited Traits – characteristics passed down from parents to offspring (a flower’s petal
color, eye color) can be dominant or recessive. The dominant trait usually shows up unless
two recessive genes are passed to the offspring.
Learned Traits – skills an organism can learn to do (seal balancing a ball on his nose)
Roles of Organisms
Predator – hunts other organisms for food (lion, shark) usually a carnivore
Prey – organism that is hunted for food (zebra, rabbit, deer)
Scavenger – gets food from dead and decaying animals (vulture)
Producer – Plants that make their own food from sun, water, and CO2
Consumers – Animals that have to find food by eating other organisms (humans)
Decomposers – get food from dead and decaying matter (bacteria and fungi)
Food Chains
Food Chain – the movement of energy (food) throughout an ecosystem
when one organism eats another (arrow points to the animals that is taking the
energy). Food chains always start with plants.
Food Web - many food chains combined; arrows show how the energy moves from one
organism to another. It shows how some animals compete for food.
Plants
All food chains start with plants (the sun gives energy to the plants).
All organisms depend on plants. A plant starts as a seed, grows roots, sprouts,
produces fruit, reproduces, and then dies.
Part of Plant
Roots
Stems
Leaves
Animals
Purpose
Absorb water and nitrogen from soil,
anchors plant in the ground
Supports plants and allows nutrients to
travel to rest of plant (grows with time – tree
rings)
Take in sunlight and carbon dioxide to
make food (sugar), contain chlorophyll,
gives off oxygen
Animals take in oxygen given off by plants and use oxygen and sugar to make carbon dioxide that plants need.
Some animals (frogs, butterflies, and other insects) change shape from baby to adult
Metamorphosis Egg-Larva-Pupa-Adult
Other animals give birth to babies that look similar to the adult (people, dogs)
Metamorphosis
Complete
Stages
Egg, Larva, Pupa,
Adult (ELPA)
Egg, Nymph, Adult
Incomplete
None
Type of Animal
Herbivore
Carnivore
Omnivore
Food
Plants
Meat (other animals)
Plants and animals
Example
Butterfly, Frog, Most
insects
Grasshopper
Humans, Dogs
Example
Rabbit, cow,
Lion, snake, owl
Bear, people
Matter and Energy
Matter – anything that has mass and takes up space; can be classified (grouped) based on properties (characteristics)
Property
Description
Tool / Example
Physical state
Solid, Liquid or gas (changes when heat is added
or removed)
Magnetism
Conduction
Mass
Weight
Volume
Density
Attracted to a magnet
Carries heat, electricity, sound
How much matter is in an object (grams)
Determined by the pull of gravity
How much space an object takes up (liters)
More dense – sinks in water / Less dense – floats
in water (salt changes the density of water)
Iron, nickel, cobalt, steel
Metal – conducts / Plastic, paper, rubber - insulates
Balance
Scale
Graduated Cylinder, Beaker
Substances like water boil and freeze at different temperatures
Boiling Point
Change from liquid 100˚ C
to gas
Freezing Point
0˚ C
Change from a
liquid to a solid
States of Matter
State
Example
Solid
Ice
Liquid
Water
Gas
Steam( water vapor)
Energy (Molecule Movement)
Very little- molecules packed tightly - vibrate
Medium – molecules slip and slide - flow
High – molecules move freely and rarely touch
Shape
Keeps its shape
Takes shape of container
Spreads out to fill entire space
When an object gains energy (heat) the molecules begin to move faster.
Mixtures and Solutions
Mixture – two or more substances mixed together, but can be separated.
Solution – when one substance gets dissolved into another substance. It looks the
same throughout (salt in water or chocolate in milk)
FORCE MOTION AND ENERGY
Form
Potential
Kinetic
Chemical
Mechanical
Description
Stored energy – no motion taking place
Energy in motion
Energy created from chemical combinations
Energy that moves objects
Electrical
Sound
Energy that passes through a circuit
Sound created from molecules vibrating. The more
molecules, the better sound travels. Sound moves best
through solids because the molecules are densely packed
Example
Book on a shelf, on top of a rollercoaster
Falling book, rollercoaster moving
Battery, food
Bicycle, simple machines (lever, wedge, screw,
wheel and axel, pulley, inclined plane, gears)
Radio, hairdryer, TV
Drum, wind chime,
Light
Bounces off objects so we can see them.
Thermal
Solar
Energy from heat
Energy from the sun (can be converted to electricity)
Sun (heat and light), flashlight (chemical and
light), campfire (heat and light)
Toaster (electrical and thermal)
Photovoltaic Cell (solar cell)
Electricity
Electricity – energy that travels through a circuit, and can be converted into other types of energy (heat - blow dryer, light - lamp
or sound - radio)
Circuit – a closed system that allows electricity to flow through it. Make up of a source (batter), path (wires), load/resistor (light bulb), and
switch (turns on and off)
Conductor – will allow heat and electricity to travel through it (metal)
Insulator – will not allow heat or electricity pass through it (plastic, rubber, wood)
Series circuit – there is only one path for the electrons to travel through, so if you remove one bulb, the others will go out.
Parallel circuit – there is more than one path for the electrons to travel through, so if you remove one bulb, the others will still work – they
will even get brighter.
Battery – uses chemical energy to produce electricity
Circuit
Series Circuit
Parallel Circuit
Light
In order to see an object, you must have light. Objects can either be transparent, translucent or opaque.
Transparent
All light passes through – light is refracted
Glass, water, lenses
Translucent
Some light passes through – some light refracted, some reflected
Tinted windows, sunglasses
Opaque
No light passes through – all light reflected
Mirror, table, book,
Light can either be reflected or refracted.
Reflected
Light bounces off the object (mirror)
Refracted
Light passes through the object, but is
bent causing the image to look different
(lens)
Lens - a transparent object used to refract light (hand lens, microscope, telescope, and camera)
Convex
Causes an image to
Hand lens, microscope, drop of
appear larger
water, eyeglasses
Concave
Forces
Causes an image to
appear smaller
Some eyeglasses
Force – a push or a pull on an object. A force is needed to start a motion, stop a motion, or change the direction of a motion.
• Objects at rest, stay at rest until moved by a force.
• Objects in motion, stay in motion until stopped by a force.
Mass - affects how much force is needed to move an object. A bowling ball takes more force to move than a baseball.
Gravity – a force that pulls objects towards one another
Friction – when two objects rub together it causes motion to slow down or stop and will produce heat.
EARTH AND SPACE
Solar System
Our solar system is made up of the sun and all the objects moving around (orbiting) it. Sun, Rocky inner planets: Mercury,
Venus, Earth, Mars, (asteroid belt); Gas Giants: Jupiter, Saturn, Uranus, Neptune; Dwarf planet: Pluto
Sun – the largest object in our solar system. It is a big ball of burning gas (star).Its gravity is strong enough to keep all the planets in orbit
(revolving) around it.It provides heat and light to Earth. Darker spots (sun spots) are cooler regions on the surface of the sun.
Moon Characteristics
Earth Characteristics
No atmosphere or water
Has an atmosphere and water
Inner core, mantle, crust
Inner core, outer core, mantle, crust
Craters
Has some craters, but not as many as the moon because of the protective
atmosphere
Moon’s gravity causes two tides a day on Earth
Earth’s gravity keeps the moon orbiting around it
Takes a month (29.5 days) to orbit the Earth
Orbits the sun once a year (365 days)
Goes through phases as it orbits Earth (takes about 1 month to go from Is tilted (seasons) and spins (rotates) on its axis once every 24 hrs (day /
full moon to next full moon)
night)
Has 1/6 the gravity of Earth
Is tilted and spins on its axis very slowly
Reflects sunlight off its surface
4 times the size of the moon
Only planet with life
Third planet from the sun
Rotation: spinning on its axis. It takes the earth 24 hrs to rotate once on its
axis. It takes the moon about 1 month to rotate once on its axis.
Revolution: orbiting around another object. It takes the earth 365 days to
revolve around the sun. It takes the moon about 1 month to revolve around
the earth.
Properties of Sediment
Particle size
Properties of Particles
Clay (finest)
Individual particles only visible with a microscope
Silt
Very fine particles. Has to be separated from sand by settling out with
water. Feels smooth and powdery when dry.
Sand
Visible particles
Gravel(largest)
Soils
How Water Passes Through Particles
Not at all
medium
medium
easily
*Soil is a mixture of many materials including sand, clay, rocks, water, fungi, bacteria, and decayed plants and animal material (humus).
There are different types of soil based on the mix of materials found in each type.
Humus
Loam
Decaying organic matter
Equal parts: sand, silt, clay humus
*Soils with a large amount of clay and decayed material will hold more water than sandy soils.
Best for planting
Earth’s Surface
Changes - The earth’s surface is constantly changing. Some changes occur quickly as a result of earthquakes and
volcanoes. Some occur slowly as a result of weathering and erosion.
Weathering
The breaking down of rock into smaller sediment (biological – plant roots, chemical or physical)
Erosion
Water, wind or gravity moves loose sediment to another place.
Deposition
Moving eroded rock and soil to a new place. The sediment will form layers. Oldest layer is onthe bottom and the youngest on
the top (will sometimes have fossils)
Landforms – caused as a result of weathering, erosion and deposition
Mountains, beaches, glacial valleys (created by moving glaciers), volcanoes, canyon (created by water erosion from a flowing river),
island, sand dune (created by wind erosion), delta (created at the mouth of a river by deposition of sediment)
Natural Resources
Renewable – these can be replaced over time (plants, animals, water, air)
Nonrenewable – once these are gone, they cannot be replaced. (coal, oil, natural gas, minerals)
Fossil fuels - made from dead plants and animals millions of years ago. (coal, oil, natural gas)
Foramtion of fossil fuels- dead plants and animals begin to decay and are covered by many layers of sediment. The layers of sediment add a
great deal of heat and pressure. After millions of years the dead plant and animal material is transformed into fossil fuels like coal, oil and natural
gas.
Alternative Energy Resources
Wind energy: energy that comes from harnessing the movement of air (wind turbines)
Solar energy: energy that comes from the sun (use of solar panels)
Hydroelectric energy: energy that comes from harnessing the movement of water ( dams)
Geothermal energy: heat energy from deep inside the earth
Biofuel: fuel made from burning of organic material like plant and animal waste
Weather and Climate
Term
Description
Weather
The day to day conditions of a particular area. (changes, short time period)
Climate
The average weather for an area over a long period of time
Precipitation
Rain, sleet, snow or hail
Vapor
Gas form of water
Evaporation
Caused by the sun heating up water and turning it to vapor
Condensation
The cooling off of water vapor and turning it back to a liquid (clouds)
Water Cycle
Movement of water between Earth’s surface and air. It is powered by the sun.