ecosystem: the mix of all living (biotic) and nonliving...

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1. Read, understand, and follow all safety instructions. 2. Check with a teacher for special directions before beginning. 3. Follow directions and only use the equipment as instructed. 4. Locate and use all required safety equipment, including: Safety Goggles: protect eyes from splashing or hot liquids Safety Apron= protect clothes from splashing or hot liquids Mitts= protect skin from hot surfaces and equipment 5. Pour acid into water, not water into acid. 6. Keep the correct spatula and/or stopper with its container. 7. Report all accidents, spills, and broken glass to the teacher. 8. Avoid eating or drinking anything in the laboratory. 9. Keep water away from electrical equipment. 10. Keep hair and clothing away from fire. 11. Clean up your area, tools, and hands when done. Beaker; container with liquid level marks; In this 100 mL provides less precise volume measurement graduatedÿ than the graduated cylinder cylinder, Graduated Cylinder: tube with level each marks; observe liquid volume from mark is bottom of the meniscus (curved surface) 10 mL. Water Displacement Method= to find the volume of an irregular shape, The submerge the object in a graduated volume cylinder containing liquid of liquid = 43 mL the object's volume = final volume - initial volume Metric System: based on factors of 10; often used for measurements; need more of "small" unit to equal "large" unit kilo hecto deka base deci centi milli 1,000 100 10 1 0.1 0.01 0.001 Large Unit < > Small Unit Examples: 1 kiloliter = 1,000 liters 60 milligrams = 6 centigrams cO Lt3 O', 5. Collect, organize, and think about your observations; can use your senses (like sight or smell) or tools (like a ruler or thermometer). 6. Use or make models (simple representations used to help you understand data or ideas better; they are not perfect). 7. Make a conclusion= Do results support your hypothesis? Equipment Binoculars Collection Net Compass Dissecting Tool Hand Lens Hot Plate Microscope Petri Dish Description make distant objects look larger and closer catches specimens (samples) tells directions (north, south, east, west) helps to cut, observe, and examine specimens makes small objects look bigger heats chemicals in the laboratory makes very small objects look much bigger allows someone to make observations or grow bacteria (often a shallow, clear dish) Stopwatch measures time precisely Telescope helps person see objects in the sky Test Tube holds chemicals (glass tube with closed end) Water Test Kit analyzes water properties Measurement Basic Metric Unit Tools Volume liter (L) graduated cylinder Length meter (m) ruler or meter stick Force Newtons (N) spring scale Temperature Celsius (°C) thermometer Mass gram (g) double pan balance triple beam balance A 1. Begin with a problem or question. 2. Learn and collect information about your question. 3. Make a hypothesis: an educated guess about what might happen; must be able to be tested; not just an opinion. 4. Design and conduct an experiment to test your hypothesis. Variable= thing that can be changed in an experiment; be sure to change only the variable you are testing Control Group: used to compare experiment's results to; the "normal" conditions :)i :". Hypothesis: The more fertilizer a plant is given, the taller the plant will grow. Not a Hypothesis: Roses are prettier than tulips. Variable: The amount of fertilizer the plants get. Control Group: Plants that did not get fertilizer. Average: add the values and divide by the number of items Hypothesis: educated guess about what may happen; sup- port hypothesis with repeated experiments/large sample size hlference: reasonable statement based on observations/clues Example; You observe that the distance between an animal's footprints increased. You infer that the animal began running. Prediction= a guess about what will happen next based on observations and your own experiences Theory: explanation based on many observations and data hÿdependent Variable: variable that is changed during the experiment; shown on x-axis (horizontal axis) Dependent Variable= variable that responds to the independent variable; its value is measured and dezoends on the independent variable's value; shown on y-axis (vertical axis) Table= uses columns and rows to organize information Circle Graph: uses a circle to show parts of a whole f'ÿ% .4ÿ Example: Table Example: Circle Graphÿ' Flower Number of Bee Visit Results Bee Visits Flower B Flower A 30 Flower B 15 Flower C Ftower C 15 50% Flower A Bar Graph= shows data in different categories using bars Line Graph= plots and connects data points on a graph; shows a trend (often over time) Example: Bar Graph Flower Results Number 30 of Bee 20 Visits 10 0 A B C Type of Flower Example: Line Graph Flower A Results Number 15ÿ of Bee 104 Visits 0 1 2 3 Day Questions: 1) In the line graph above, what is the indeEeÿz dent variable? 2) What is the dependent variable? 3) Do the bee visits increase, decrease, or remain constant over time? Answers: 1) day 2) number of bee visits 3) decrease Contour Map: lines connect points of equal elevation (height above sea level); the closer the lines are spaced, the steeper (greater) the change in elevation Example= Topographical Contour Map Which point is steeper, A or B? A

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Page 1: Ecosystem: the mix of all living (biotic) and nonliving (abiotic)crjh8thgradescience.pbworks.com/w/file/fetch/58110680... ·  · 2018-03-01Avoid eating or drinking anything in the

1. Read, understand, and follow all safety instructions.2. Check with a teacher for special directions before beginning.3. Follow directions and only use the equipment as instructed.4. Locate and use all required safety equipment, including:Safety Goggles: protect eyes from splashing or hot liquidsSafety Apron= protect clothes from splashing or hot liquidsMitts= protect skin from hot surfaces and equipment5. Pour acid into water, not water into acid.6. Keep the correct spatula and/or stopper with its container.7. Report all accidents, spills, and broken glass to the teacher.8. Avoid eating or drinking anything in the laboratory.9. Keep water away from electrical equipment.10. Keep hair and clothing away from fire.11. Clean up your area, tools, and hands when done.

Beaker; container with liquid level marks; In this 100 mLprovides less precise volume measurement graduatedÿthan the graduated cylinder cylinder,Graduated Cylinder: tube with level eachmarks; observe liquid volume from mark isbottom of the meniscus (curved surface) 10 mL.Water Displacement Method= to findthe volume of an irregular shape, Thesubmerge the object in a graduated volumecylinder containing liquid of liquid = 43 mLthe object's volume = final volume - initial volumeMetric System: based on factors of 10; often used formeasurements; need more of "small" unit to equal "large" unit

kilo hecto deka base deci centi milli1,000 100 10 1 0.1 0.01 0.001

Large Unit < > Small UnitExamples: 1 kiloliter = 1,000 liters

60 milligrams = 6 centigrams

cO

Lt3

O',

5. Collect, organize, and think about your observations; canuse your senses (like sight or smell) or tools (like a ruler orthermometer).

6. Use or make models (simple representations used to helpyou understand data or ideas better; they are not perfect).

7. Make a conclusion= Do results support your hypothesis?

EquipmentBinocularsCollection NetCompassDissecting Tool

Hand LensHot PlateMicroscopePetri Dish

Descriptionmake distant objects look larger and closercatches specimens (samples)tells directions (north, south, east, west)helps to cut, observe, and examinespecimensmakes small objects look biggerheats chemicals in the laboratorymakes very small objects look much biggerallows someone to make observations orgrow bacteria (often a shallow, clear dish)

Stopwatch measures time preciselyTelescope helps person see objects in the skyTest Tube holds chemicals (glass tube with closed end)Water Test Kit analyzes water propertiesMeasurement Basic Metric Unit Tools

Volume liter (L) graduated cylinderLength meter (m) ruler or meter stickForce Newtons (N) spring scaleTemperature Celsius (°C) thermometerMass gram (g) double pan balance

triple beam balance

A

1. Begin with a problem or question.2. Learn and collect information about

your question.3. Make a hypothesis: an educated guess about what might

happen; must be able to be tested; not just an opinion.4. Design and conduct an experiment to test your hypothesis.

Variable= thing that can be changed in an experiment; be sureto change only the variable you are testingControl Group: used to compare experiment's results to; the"normal" conditions

:)i :". Hypothesis: The more fertilizer a plant is given, thetaller the plant will grow.Not a Hypothesis: Roses are prettier than tulips.Variable: The amount of fertilizer the plants get.Control Group: Plants that did not get fertilizer.

Average: add the values and divide by the number of itemsHypothesis: educated guess about what may happen; sup-port hypothesis with repeated experiments/large sample sizehlference: reasonable statement based on observations/clues

Example; You observe that the distance between an animal'sfootprints increased. You infer that the animal began running.

Prediction= a guess about what will happen next based onobservations and your own experiencesTheory: explanation based on many observations and datahÿdependent Variable: variable that is changed during theexperiment; shown on x-axis (horizontal axis)Dependent Variable= variable that responds to theindependent variable; its value is measured and dezoends onthe independent variable's value; shown on y-axis (vertical axis)Table= uses columns and rows to organize informationCircle Graph: uses a circle to show parts of a whole f'ÿ% .4ÿExample: Table Example: Circle Graphÿ'Flower Number of Bee Visit Results

Bee VisitsFlower B

Flower A 30Flower B 15 Flower C

Ftower C 15 50% Flower ABar Graph= shows data in different categories using barsLine Graph= plots and connects data points on a graph;shows a trend (often over time)Example: Bar Graph

Flower ResultsNumber 30of Bee 20Visits 10

0 A B CType of Flower

Example: Line GraphFlower A Results

Number 15ÿof Bee 104Visits

0 1 2 3Day

Questions: 1) In the line graph above, what is the indeEeÿzdent variable? 2) What is the dependent variable? 3) Do thebee visits increase, decrease, or remain constant over time?Answers: 1) day 2) number of bee visits 3) decrease

Contour Map: linesconnect points of equalelevation (height abovesea level); the closerthe lines are spaced,the steeper (greater) thechange in elevation

Example= Topographical Contour Map

Which point is steeper, A or B? A

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Organisra= a living thing (plant or animal)Needs: organism's requirements to survive (like food, water,living space); organisms depend on other organisms and theirhabitat to meet their needs (birds use twigs to build nests)Competition: a struggle for a limited amount of resources; anorganism must have a way to get what it needs (food, water,oxygen) or it will die (plants in a jungle compete for sunlight)Ecosystem: the mix of all living (biotic) and nonliving (abiotic)things and conditions in an area (like temperature, animals, etc.)Environment: surrounding conditions; different environmentssupport different types of organismsSpecies= organisms with similar characteristics, live in samearea, and breed with each other (Monarch butterfly) to producefertile offspring; may naturally live (native) or not naturally live(invasive) in ecosystemPopulation: organisms that are of same species, live in samearea, and breed with each other (Monarch butterflies in acertain forest)Community: all the populations that live and interact in anarea (all the animals and plants that live in a certain forest)Habitat: area an organism lives in and gets what it needs (lake)Niche: the role a species has in an ecosystem (squirrelsconsume acorns from trees)Ecological Succession: gradual replacement ofplants and animals over time due to environmentalchanges (new species of trees replace the old treesthat burned down in a forest fire)

Food Chain= describes how energy is passed from oneorganism to another; energy originates from the Sun and ispassed to producers and then to consumers; energy moves inthe direction of the arrow from one organism to the otherFood Web: picture that shows the many food chains in anecosystem; arrows show the direction energy moves (a hawkgets energy by eating a rabbit, mouse, or small bird)

Food Web

Type of Animal Source of Food Example

Herbivore plants cowCarnivore animals (meat) wolfOmnivore plants and animals bear

Term Role Example

Predator hunts/eats other organisms lionPrey hunted as food rabbitScavenger gets food from dead animals vultureProducer makes own food plantsConsumer gets food from other organisms animalsDecomposer gets food from dead organisms fungi

or the waste of organismsSyiÿabiosis: close association between two (or more)organisms; may be beneficial, harmful, or neutral (no effect)Relationship Organism #1 Effect Organism #2 Effect

Parasitism good (+) bad (-)Mutualism good (+) good (+)Commensalism good (+) no effect

Traits: an organism's characteristics (eye color, height)inherited Trait: characteristic passed from parent to offspringthrough genesAdaptation: trait that helps an organism live and meet itsneeds better; organisms may use colors, smells, or poisons toblend into their habitat or protect themselves

Example: The bad scent of a skunk's spray helps tokeep predators away from it.

Natural Selection: process by which organisms with certainfavorable traits survive and reproduce more successfully thanothersEvolution= changing of a species' traits over many yearsBehavior: the way an organism does something or actsinherited Behavior: behavior an organism is born with; notlearned Example: breathingLearned Behavior: behavior an organism is not born with;must be learned Example: reading

small bird,

Extinct: if a species cannot get what it needs, it will die out(T. rex dinosaur)Endangered= if a species cannot get what it needs, thenumber will get smaller and over time may become extinctImpacts on Organisra Populations: effects on populationscaused by the amount of food, water, disease, predators, etc.Human impact: humans can change an ecosystem in badways (like through air/water pollution) or in good ways (likeconservation); impacts can be short or long termEnvironraental Changes= changes in the environment canaffect the survival of an organism or species

Example= If a river dries up, the fish will die andthe food supply for bears will decrease. The bearpopulation will decline unless the bears find adifferent food source.

Limiting Factors: factors that control a population's size

Examples: food, water, living space, shelter

Carrying Capacity= maximum population that can live in anarea over a long period of time (controlled by limiting factors)

During photosynthesis, plants transform the Sun's energy (light)into chemical energy in the form of glucose. Animals eat plants(or other animals that have eaten plants) and use the glucose.Carbon Dioxide=Oxygen Cycle: during photosynthesisplants produce the oxygen that animals need; duringrespiration animals produce the carbon dioxide that plantsneed

carbonPhotosynthesis

r dioxideÿ ÿ

,ÿ. -ÿÿ ÿ glucose(sugar)

radiantenergy fromthe Sun plants

water oxygen

6H20 + 6CO2 light energy C6H1206 + 602water + carbon dioxide produces glucose + oxygen

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Nitrogen is needed by living things. Bacteria change thenitrogen in the air into a form that plants can get and use fromthe soil. Animals get nitrogen by eating plants. Decomposersreturn nitrogen from dead plants and animals back to the soil.

Cell= smallest unit of living things- all organisms are made of one or more cells- cells have functions (jobs) that help keep the organism alive- cells contain smaller structures that each have a function

(_cell walls and chloroplasts are structures unique to plant cells)Nucleus: the "brain" of the cell; controls the cell's activitiesand contains chromosomes made of DNAStructure and Function-" the structure (overall makeup of anorganism or a part of it) can help with its function (job)Example: cell membranes are made of layers of fat and proteinwith small pores (structure) which allow the membranes tocontrol what enters and leaves the cells (function)

Diffasion: movement of molecules from area of hiÿherconcentration (amount) to lower concentrationOsmosis: movement of water from areas ofconcentration to lower concentration until cell equilibrium(stability) is reached; the cell membrane (outer layer) controlsthe flow of molecules in and out of the cellTurgor Pressure." pressure inside a plant cell caused by theosmotic flow of water into the cell; allows plants to remainupright; without turgor pressure the leaves would sag or wilt

Homeostasis: ability of an organism or its systems to maintaininternal equilibrium (stability or balance) using chemicalreactions and physical processes (feedback mechanisms)Feedback Response to Stimulus ExampleNegative decreases effect a body that is too hot,

will try to cool itself downPositive increases effect presence of stomach acid

increases its production

Example: Homeostasis - Body Temperature Control

Body Temperature Feedback Mechanism

Too hot sweat, blood vessels dilate(get bigger) to allow heat out

Too cold shiver, blood vessels constrict(get smaller) to keep heat in

Body Systems Work Together to Control Temperaturebrain detects body temperature is too low ÿ

\nervous system sends signals

/ \dermal (skin) blood vessels muscles contract

constrict (shiver)

Living things build and organize themselves from small andsimple (atom) to complex systems (communities).

Examples: a group of cells that do certain functions make up atissue; a group of tissues working together make up an organ

Levels of Organization

Basic

Term

atommoleculecelltissue

organorgan systemorganism

populationcommunity

Example

oxygenwaterred blood cellmuscle tissueheart

circulatory

personpeople in a certain cityall populations in a city

System and Paris." properties of a system can be differentfrom those of its parts; systems depend on interaction of partsmnteractien ameng Systems: often many systems mustinteract to perform a function (like in the human body)

Example: A person can exercise only because several organsand organ systems interact. A person (using his/her brain)decides to exercise. The nervous system sends a signal to themuscles to begin moving. The circulatory system beginspumping blood faster to provide more oxygen to the body.

Complex

Heredity: the passing of traits from one generation to the nextGene: piece of DNA that represents the basic unit of heredityÿDNA: contains genetic information that controls acell's activities; found in the nucleus of organism's _ÿ"cells; can be inherited only through sperm and egg cellsÿY-Chromosome' structure found in cell's nucleus; contains DNAAllele= form of a gene that controls a characteristicTrait: organism's characteristics (eye color, height)Selective Breeding: purposely selecting organisms to matein order to produce offspring with certain characteristicsDerainant Trait= trait that appears when at least onedominant allele is inherited; represent allele with capital letterExample" RRecessive Trait: trait that appears when two recessive allelesare inherited; represent allele with lowercase letter Example: rGenotype= inherited combination of alleles; represented bytwo letters Examples: RR, Rr, or rrPhenetype: organism's appearance based on its genotypeExample: red petals on a flower

Example: Genotype and PhenotypeLet R represent the dominant allele of red petalsand let r represent the recessive allele of white petals

Phenotype ReasoningRR red petals two dominant allelesRr red petals one dominant allelerr white petals two recessive alleles

Punnett Square: diagram that helps to predict the possiblegenotypes and phenotypes of offspring

Example: Punnett SquareB is dominant allele (brown hair)b is recessive allele (blonde hair)

Father, BbB b

Mother, BB BbBb Bb bb

Possible CombinationsGe no_ÿ Phenotype

BB (¼) brownBb (ÿ) brownbb (¼) blondeThere is a ÿ (or 75%)chance the offspring willhave brown hair, and25% chance it will haveblonde.

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bVlatÿer: anything that has mass and takes up space;makes up all things (living and nonliving) in the world;classified by properties, or characteristics, including:

Property

StateMassWeightVolumeDensityMagnetism

Conduction

Term

Boiling PointFreezing Point

Description

form of matter (solid, liquid, or gas)amount of matter in an object (grams)amount of gravity on object (Newtons)amount of space object takes up (liters)mass divided by volume (grams/liter)ability to be attracted, or pulled, tomagnetsability to carry heat, electricity, andsound (opposite is called insulation)

Changes in State Water

from liquid to gas 100 °Cfrom liquid to solid 0 °C

(;heraical Symbeh element's abbreviation; first letter iscapitalized and second letter (if has one) is lowercase

Examples: N for nitrogen, 0 for oxygen, Au for gold

Chemical Formula: substance's abbreviationSubscript: number at the lower right of element's symbol(shows number of atoms); if no subscript, there is 1 atom

Example: H20 has 2 hydrogen atoms and 1 oxygen atom

Periodic Table: chart of elements, arranged in rows inincreasing atomic number (the number of protons in theelement); elements in the same column (group) are similar

Periodic Table

N4Mgl si P s 01 ArK CaSe Ti V CrMn FeCo Ni Cu ZnGaGeAs Se Br KrRb Sr Y Zr NbMoTc RuRh PdAgCd In SnSb Te I XeCs Ba Laÿf Ta W ReOs Ir Pt Au Hg TI Pb Bi Po At RnFr Ra Ac\Fÿ Db Sg Bh Hs Mt

Ce Pr Nd PrnSrn Eu Gd Tb Dy H0 Er Tm Yb LuTh Pa U NpPuAmCmBk Cf EsFmMdNo Lr

Atoms are the very small substances (building blocks) ofall matter. The nucleus is the central part of the atom andcontains most of its mass. An atom has three main parts.

Atom Part Location Charge

Proton in nucleus positive (+)Neutron in nucleus neutral (no charge)Electron outside nucleus negative (-)

Example: Model of a Helium Atom/-ÿ-<ÿ\ electrons (2) travel in a cloud

(/ (ÿÿ around the nucleus\ "-ÿ J-'--protons (2)

neutrons (2)

Examples: methane (CH4) is made of 1 carbon and 4hydrogen atoms; ozone (03) is made of 3 oxygen atoms

Oeÿpound: substance made of two or more elements

Example: salt (NaCI) is made of sodium and chlorine

ixtÿre: two or more substances blended together;because they do not make a new substance, they keeptheir own physical properties; can be separated

Examples. salt and pepper mixture, salad

Sehÿtien: mixtures that are blended so well that theirproperties are the same throughout; one substancedissolves into the other

Examples: salt dissolved in water; chocolate syrupdissolved in milk

Emerÿer, t: substance made of only one kind of atom

Examples: carbon, helium, iron, potassium, calcium

emecule: substances made of more than one atom

State Atom Movement Energy Shape

solid small distances low fixedliquid larger distances medium container's shapegas great distances high fills space

When matter absorbs energy, its atoms move faster andthey spread apart from each other. Atoms are packedclosest together in solids and farthest apart in gases.

Example: Helium's Data from Periodic Table

2 4ÿ--- atomic number (number of protons)Heÿ-- symbol

4.0026 -- atomic mass (protons + neutrons)Helium-ÿ--- name

Element Type Location on Periodic Table (ÿ"ÿ4Jÿ/

Metal left side Lÿ-ÿ.ÿ])Nonmetal right side "4#--Metalloid along the zigzag line (stair step)iVletals: shiny, can be bent or pulled, good conductors ofheat/electricity; many are solids at room temperatureNonmetals: dull, brittle, poor conductors of heat/electricity; many are gases at room temperatureMetalloids: conducts electricity under some conditions

Law ef Conservation ef Mass: mass is not created ordestroyed in an ordinary chemical reaction

total mass of reactants = totat mass of productsPhysical Change: change in size, shape, or state; stillsame substance (steam and ice are both water)C;hemical Reaction: process in which one or moresubstances change to produce a new substanceChemical Equation: gives the number and kind ofsubstances involved in a reaction; reactants are thestarting materials and products are the final materials

Example" reactant + reactant yields product2Na + Cl2 ---> 2NaCI

Exothermic Reaction: gives off (produces) energy

Example: 2Na + CIÿ ---> 2NaCl + energyIEndetherraic Reaction: takes in (absorbs) energy

Example: Nÿ + O2 + energy --ÿ 2NOSpecific Nleat: the amount of energy needed to changethe temperature of 1 gram of a substance by 1 °C

Example: Water's specific heat is about five times greaterthan land's specific heat. Large bodies of water, likeoceans, store large amounts of heat from the Sun. Sincewater heats and cools more slowly than landmasses,temperature differences can cause thermal wind systems(cool air replaces warmer air).

Sea Breeze: daytime wind from ocean to landLaÿd Breeze: nighttime wind from land to ocean

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Energy: ability to move or change matter (do work)Potential Energy; energy of position (stored energy)

Example: a rock resting on a mountain has morepotential energy than a rock resting on a small hill

Kinetic Energy: energy of motion "]

Example: a rock rolling down a hill

Motion: change in position over certain amount of timeSpeed= rate at which object moves

Speed ::: distaÿce + timeVelocity-" describes speed in a given directionAcceleration= rate at which velocity changes

Energy Form

ChemicalMechanicalElectricalSoundLightThermalSolar

Description

stores energy in molecules/bondsmoves objectsmoves electrons through circuit wiresvibrates; makes a sound in an eartravels as a waveproduces heat; due to motion of atomsprovides most of the Earth's energy;generated by the Sun

Example: Speed Constant Speed Graph

distance, time, speed, 75ÿ /=m s m/s E0 0 0 ÿ 5025 1 25

60 2550 2 2575 3 25 >

Does distance increase, decrease, or 0 1 2 3remain constant over time? increase time, s

Energy can be transformed (changed) from one formto another. People transform energy to meet their needs.

Examples:e Chemical energy from gasoline is converted to

mechanical energy when you drive a car.e Electrical energy is converted to light energy iÿ '

when you turn on a lamp. "/ ÿ ,.,¢ Mechanical energy from wind is converted to

electrical energy in windmills.¢ Chemical energy from batteries is converted to sound

energy when you turn on a radio.

Balanced Forces= opposing forces are equal in size;does not change the speed or direction of an object

Example; Balanced Forces - no motion

Example: By contracting, the heart generates a force toaccelerate a mass of blood through the body's circulatorysystem.

Force." a push or pull; force is needed to start or stop themotion of an object; depends on the mass of an object

Force = mass x acceleration

Work- force acting through a distanceWork := Fo!ce x distance

iÿlachine= tool that makes work easier by changing thesize or direction of the force put into it (input force),

Simple MachineInclined PlaneWedge

ScrewLever

Pulley

Wheel and Axle

Description

slanted surfaceinclined plane that moves (like aseedling root tip pushing into the soil)inclined plane wrapped around a barrigid bar that moves about a fixedpoint, called the fulcrumrope, chain, or belt wrapped arounda grooved wheeltwo circular objects of different sizes;the force applied to the wheel istransferred to the axle

Screw (screw)

Simple Machine Examples

Inclined Plane (ladder) Wedge (chisel)

Lever (hammer) Pulley (well) Wheel and Axle (wagon)

Unbalanced Forces= opposing forces are not equal insize; can change the speed and/or direction of an object

Example: Unbalanced Forces - motion in thedirection of the greater force ,ÿ

move to the left

Resistance Force: force, like friction, opposing motionGravity: a force that pulls objects in the universe towardone another; gravity varies by location; the Earth's gravityis greater than the moon's gravity so a person weighs moreon the Earth than on the moon (but mass is the same)Weight." measures the force of gravity on an object; theacceleration due to gravity is 9,8 m/s2

Weir;hi -ÿ mass x gravity

Wave." disturbance that transmits energy/ledium." substance (like solid, liquid, or gas) through

which a wave travelsIViechanical Waves; waves that require a medium

Examples: ocean waves through water, sound wavesthrough air, seismic waves through the ground

Electromagnetic Waves: waves that do not require amedium; can travel through a vacuum (empty space)

Examples: visible light, radio waves, and X-rays cantravel through a vacuum or through a medium

Amplitude: maximum distance from resting pointWavelength." distance between two adjacent crests(peaks) or troughs (valleys)Frequency: number of wavelengths in given time period

Example: Wave amplitude ÿ- ÿ /ÿ-ÿ-crest

resting point ÿ ' ÿtrough Jÿ}ÿ .......

wavelength

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Jniverse: space and the matter and energy it containsGalaxy: system (large group) of stars in spaceStar= huge, hot body made of different gases; radiates energy;:'a star's temperature is related to the color of light (spectra)the star gives off (based on its elements); a star's brightnessdepends on its temperature, size, and distance from EarthNebula: large clouds of gas and dust; may glow bythemselves, absorb starlight, or reflect starlightOeraet: small object made of ice with some gas, dust, androck; a "tail" can appear as the comet revolves around the Sunand is heatedPlanets: nearly round objects that revolve around a star; in oursolar system the planets that revolve around our Sun are:Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, NeptuneSun: star that is the center of our solar system; provides mostof Earth's energyIV]con: object that revolves around a planet; natural satelliteEclipse DescriptionLunar moon moves into Earth's shadowSolar moon's shadow crosses EarthTides." the dally movement (rise and fall) of the Earth's oceansurfaces; caused by the moon's pull of gravity on the EarthSpring Tide: largest difference between low and high tideNeap Tide." smallest difference between low and high tidePhases= four stages that the moon goes through when itrevolves around the Earth each month

Changes= different events cause the Earth's surface andanimal populations to change over time; can be caused bycatastrophic natural events (earthquake, volcano) or by humans(pollution, unregulated hunting, species introduction)Term Description ÿ'-ÿ,ÿFÿ;

Erosion moving rocks or soil from one place toanother due to water, wind, or gravity

Weathering breaking down of materials like rocks intosmaller pieces (soil, sand, dirt)

Deposition dropping eroded rock and soil to new locationNatural Resource= a substance that helps support life on EarthResource Type Typical Time to Replace ExamplesRenewable within a person's lifetime trees, oxygenNonrenewable millions of years oil, gas, coalInexhaustible not used up sun, wind, tidesFossil Fuels: energy sources (coal, oil, and gas) that weremade over many years from the remains of living thingsHuman Impact ExamplesNegative air, water, and soil pollution, deforestationPositive conservation, habitat preservation, recycling

New Moon(spring Tide)

moon is between the sunand earth (cannot be seen)

rLast (Third) Quarter Moon

(Neap Tide)

First Quarter Moon

(Neap[ÿ

moon appears over time asa crescent (see 1/2 of circle)

Full Moon(Spring Tide)

moon is on opposite sideof earth (see a circle)

Earth: our planet; revolves around Sun in elliptical (oval) shapeSeasons: natural divisions of the year caused by the tilt of theEarth's axis, combined with its revolution around the SunLength of Daylight: depends on latitude (distance north orsouth of equator) and season (more daylight during Summer)Equinox: the two times per year when the Sun is directly over

; length of day and night are same; in northernhemisphere occurs in March (vernal) and September (autumnal)Solstice= the two times per year when the Sun is farthest from

; in northern hemisphere summer solstice (in June) isday of year and winter solstice (December) is shortest

Sunlight IlitS m0st .... i"..b:4i i-, ÿ:,

directly at the equatorÿ ( Equator

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CycleEarth revolves around SunMoon revolves around EarthEarth rotates on its axis

Time

one year (3651A days)one month (29V2 days)one day (24 hours)

Biomass: total of all materials that come from living organismsComposting= breaking down (decaying) of dead organisms bydecomposers (like bacteria) to produce carbon dioxide, water,minerals, organic compounds, and heat

moon slowly becomes lessvisible (see V2 of circle)

Plate Tectonics: theory that the lithosphere (Earth's outermostlayer) is divided into plates that slowly but constantly moveBoundary Plate Movement Possible ResultConvergent collide > < mountain,volcanoDivergent move away < > rift valleys, earthquakesTransform slide past ÿi___> fault lines

Continental Drift: theory that continents move away fromeach other; continents may have once been connectedLand Subsidence: sinking of areas of the Earth's crust;caused by underground voids or compactionRock Type Formation ProcessIgneous hot magma cools and hardensSedimentary rock pieces deposited and compacted togetherMetamorphic existing rock changed by heat and pressureLava= term for magma after a volcanic eruption

Rock Cycle.ÿC°ÿJ-jÿ ÿ--__._£ÿ1

and heat anddeposition pressure

I Sedimentary ÿ erosion and deposition Metÿoÿpÿ{€I Rocks heat and pressure

Cloud

Transpiration

Watershed, land area which drains surface water into a bodyof water (like a stream)Surface Water= water on earth's surface (lake, stream, ocean)Ground Water: water located beneath land surface and trappedin porous rocks/soil; provides water to plants, wells, aquifers(underground reservoirs), etc.Precipitation: water that falls to Earth (rain, snow, sleet, hail)Transpiration: water vapor released into atmosphere by plantsWater Cycle= constant movement of water between the Earth'ssurface and air (goes back and forth between liquid and vapor)

Example: Condensation(vapor to/liquid)

Precipitafl0h,'

Evaporation (rain) ÿ,(liquid to vapor) ' /

RunoffHill

/: Plants