Science8—STAARReview
EarthandSpace
(3)Thestudent knows the effects resultingfromcyclical movements of theSun, Earth,and Moon. Thestudent is expected to (A) model and illustrate howthe tilted Earth rotatesonits axis, causing dayand night and revolves aroundthe Sun causingchanges in seasons, and (B) demonstrate and predict he sequenceof events in thelunarcycle.
Vocab— Torotatemeans tospinon an axis.Torevolvemeansto orbit around anotherbody.Theearth rotateseach daywhilerevolving around thesunonceper year.
Look atthepicturetotheright.Theearthistiltedabout 23degrees.This meansthat intheNorthern Hemisphereistiltedtoward the sunand hasalarg- er amountofdirect sunlight duringthesummermonthsand lessdirect sunlight during thewinter.TheNorthern and Southern Hemisphereshaveopposite seasons.
OnYour Own—Evaluatethediagramtotheleft.Whichof thefollowingstatementsistrue?
Sun
Rays
AWhentheEarth and Sunareinthisposition,itiswinterin theNorthern Hemisphere.
B WhentheEarth and Sun areinthisposition,itissummerintheNorthern Hemisphere.
C WhentheEarth andSun areinthisposition,itisspringintheNorthern Hemisphere.
DWhentheEarth and Sunareinthisposition,itisautumnintheNorthern Hemisphere.
Vocab— the Lunar cycle istheappearanceofphasesofthe Moonasviewed from
Earth,astheMoonorbitstheEarth aboutonceevery 27days.
Waxing—toincreaseinsizegraduallyCrescent—havinga concaveshape(sliver)
Waning—todecreaseinsizegraduallyGibbous—morethan half
Themoonhasnonaturalluminouscapabilities.Itonlyreflectslight fromthesun (like a mirror).Themoonphasesaredisplayed intheimagetotheleft. Noticethat during thenewmoon,themoonappearsdark.Actually,duringa newmoonthe back sideofthemoonwould belit,but fromEarth, wecan’t seethebackside. The diagramonlyshows what you wouldseeifthesunand moonwereinthoseposi- tionsrelativetotheEarth. Thepositionofthesun,moonand Earth alsoaffectsthe earth’socean and causeschangesinthetides.
YourTurn—ThepicturetotheleftdisplaysthemoonorbitingtheEarth.Anobserverisat pointX. Whichofthefollowingbest describeswhat themoonwilllookliketotheobserver?
AThemoonwillreflectthemaximumlight fromthesun.
XYBThemoonwillnot reflect any sunlightatall.
CThemoonwillonlyhavea smallcrescentlit.
DThemoonwillhavea largeamountofreflected light fromthesun.
AtpositionXthe moonwill appear as awaxing gibbous andwillbemostly light.Ifthemaximumwere lit,thenitis a fullmoon. AnswerD
Whenstandingat positionY,onwhich datewillonequarterofthemoonbelitby thesun?April 27
Whenstandingat positionY,onwhich datewillthemoon havetheleast about oflightreflected fromthesun?May16
Category3Continued….
Thestudent isexpectedtodescribecomponentsoftheuniverse,including stars,nebulae,and galaxiesand usemodelssuchasHertzsprung-Russelldiagramsfor classification.
Vocab—Nebulae—Acloudofgasand dust I outer space, visibleinthenight skiasluminouspatchesorareasof darkness. Galaxy—Asystemofmillionsofstars,alongwithgasand dust that isheldtogetherby gravitationalattrac- tion. Star—A self-luminouscelestialbody consistingofgasesheldtogetherby itsown
gravity(our sun isjusta starthat isVERYclosecompared toother stars). Hertzsprung-
RussellDiagrams(H-R)—a scattergraphofstarsshowingtherelationshipbetween the stars’ brightness,classification and temperature.
Hertzsprung-RussellDiagram
YourTurn—Based on theH-Rdiagramtothe left,which ofthefollowingstatementsistrue?
AIfastarhasatemperatureof10,000degrees anda luminosity of1 itisa WhiteDwarfstar.
B Ifastarhasaluminosity of100and a temper- atureof20,000itisa mainsequencestar.
CIfastarhasaluminosity of.01and a temper- atureof4000,it isaGiant star.
DIfastarhasaluminosity of10,000and a tem- peratureof20,000,itisa Super-Giant Star.
SUN
Our sun isa medium-sized starthat is foundintheMainSequencesection of theH-Rdiagram. Our sun is found near theedgeofa disc-shaped galaxy.
Spaceis sovast that distances aremeasured in light years (theamount oftimeit takes light totravel inone year).A light yearis about 10 trillionkilometers.
Thestudent isexpectedtorelateplatetectonictotheformationofcrustalfeatures.
Vocab—Divergent—tomoveapart. Thiscrustalfeatureisobserved inocean ridgesand sea floor spreading. Convergent—tomovetogether.This featureis observed inocean trenchesand island arcs.Transform—moveinopposite directions. Thisisobserved alongfaultlinessuchasinCalifornia. Hot spots—fixed placeswithinthe upperlayerofcrust whererocksmelttogeneratemagma.Theseare foundinthedeep ocean floorand mayriseenoughtoformislands.Seethepicturetotheright.
Thestudent isexpectedtointerprettopographicmapsandsatelliteviewstoidentifyland
anderosionalfeaturesandpredicthowthesefeaturesmaybereshaped by weathering.
Vocab— Topographicmap- atwodimensional representation ofa
3-Dlandsurface.
Erosionalfeatures
–erosion occurs wheretheforcesof naturemove soil and rockthrough water, wind,ice, gravityand the action ofplants
YourTurn— Accordingtothemapto theright,what is in between thetwohills?
ANothing, thetwohilltopsmerge. B A smallvalley.
CA very largeflatplain.
DAmajorbody ofwater.
How muchhigherisBaker Hillthan AbleHill?
Aabout 40mBabout 30m
Cabout 20mDabout 10m
Science8—STAARReview
Organismsand the
Environment
Thestudent isexpectedtodescribeproducer/consumer,predator/prey,and parasite/host relationshipsasthey occur infoodwebswithinmarine,freshwaterand terrestrial ecosystems. YourTurn—Look atthediagramtotheright. How manyproducer/consumer pairsdo
you see?
Plantsand phytoplankton areproducersand thegrasshopperand thezooplankton aretheconsumers. Twopairs.
How manypredator/preyrelationshipsarethereinthediagram? Hawk/snake,snake/
mouse,mouse/grasshopper,Orca/largefish,largefish/smallerfish. Fivepairs.How mayparasite/hostrelationshipsareshown inthediagram? None.
Exampleofparasite/host wouldbefleason themouse,barnacleson thewhale,tapeworms
ina human oraphidson a plant.
Onyourown—Mistletoeisa plant that attachestosometreesinNorth Central Texas. Themis- tletoe will slowthegrowthofthetree,sinceitusessomeof thetree’swaterand nutrients. Which pair oftermsbest describestherelationshipbetween themistletoeand thetree?
Apredator/prey B parasite/host Cconsumer/producer Dherbivore/carnivore
Thestudent willinvestigate howorganismsand popula- tionsinan ecosystemdepend on and maycompeteforbiotic andabioticfactors suchas quantity oflight,water,range oftemperaturesorsoilcompo- sitionand thestudentswill explorehowshort and long
temenvironmentalchanges affectorganismsand traitsin subsequent populations.
YourTurn—Accordingtothepicture,which ofthefollowingstate- mentsismost valid?
ATheorganismsinthisecosystemshowavariety of organismsand species.
B Theorganismsinthisecosystemdonot need
tocompeteforabioticfactors.
Autotrophs—can make their own food from light or chemical energy. Plants are autotrophs.
Vocab—Bioticfactors—arerelated tolifeorlivingfactorssuch as plants,animals,fungi,protest and bacteria.
AbioticFactors—arenon livingfactorsinan environment such
ashabitat, weather,sunlight,oxygen orotherimportantele- ments.
Bioticand Abioticfactorscombinetomakean ecosystem whichisa community ofliving and nonlivingthings.Ifa single factor ischanged inan ecosystemduetohuman intervention ofa naturalevent, thewholesystemcan bealtered.
Onyourown—At onetime largeherdsofBisonroamed acrosstheUS.Brown-headedcowbirdsfollowedtheBison andcaptured theinsectsthat scatteredasthebison walked through thegrass.ManyoftheBisonwerekilledby early American hunters.Whichofthefollowingisthemostcor- rectstatement about what mightoccur?
CTheorganismsinthis ecosystemhavea reduced amount oftheabioticfactorof water.
DTheorganismsinthisecosystemhaveplentiful rainand arenot short any oftheabioticfactors.
AThegrasses wouldnolonger growand a desert would soonform.
B Thecowbirdpopulation wouldgrowduetofewerBison.
C TheBison wouldadapt andbecomebetteratavoiding hunters.
DThecowbirdpopulation woulddiminish duetothedifficul-
tiesinfindinginsectstoeat withouttheBison.