Unit7Exam 1

ScienceUnitTest

Grade:8

Unit7:Biodiversity

1. Theclearingofrainforestsforagriculturalusehasledtoadecreaseinbiodiversityinmanyareas.Onepotentialconsequenceofdeforestationis

a. Anincreaseintheamountofatmosphericoxygen.b. Thelossofplantswithpotentialmedicinaluses.c. Adecreaseinsoilerosion.d. Improvedhabitatforwildlife.

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Unit7Exam 2

2. Apictureofafungusandaclassificationkeyareshownbelow.

Basedonthekey,whichfungusisshown?

a. Turkeytailb. Beefsteakc. Goldenchanterelled. Commonmorel

Unit7Exam 3

3. Twofossilsthatappeartobefromthesametypeoforganismarefoundintwodifferentlayersof

rock.Theylayersofrockareshownbelow.

Whichcanbedeterminedfromthelocationofthefossils?

a. Thepreyoftheorganismsb. Thepredatorsoftheorganismc. Thecauseofdeathforeachorganismd. Therelativeageofeachorganism

Unit7Exam 4

4. AnArcticenvironmenthastemperaturesthatrangebetween−22°Cand6°Cwithsnowcoveringsomeofthearea.Whichadaptationwouldmostlikelyhelpapopulationoforganismssurvivethisenvironment?

a. Longnecksandtalllegsb. Largeshellandleatheryskinc. Lightcoloredfurandlayersofblubberd. Brightlycoloredfeathersandwebbedfeet

5. Thegraphbelowrepresentstheamountofrabbitsinapopulationthathavedifferentrunningspeeds.Anewpredatorisintroducedtotheareathathasarunningspeedrepresentedbythedashedline.

Whichrabbitswillmostlikelyhaveasurvivaladvantageaftertheintroductionofthisnewpredator?

a. Rabbitsthatrunslowerthan10kilometersperhourb. Rabbitsthatrunbetween20and30kilometersperhourc. Rabbitsthatrunbetween30and40kilometersperhourd. Rabbitsthatrunfasterthan40kilometersperhour

Unit7Exam 5

6. Aclassificationkeyforanorganismisshownbelow.

Towhatclassdoestheorganismbelong?

a. Cestodoab. Gastropodac. Trematodad. Bivalvia

7. Astudentobservesatreewithsmallneedle-likeleavesthatstaygreenyearround.Whichconclusion

canthestudentsdrawfromtheshapeoftheleaves?a. Theleavesofthetreedonotperformphotosynthesisb. Theleavesofthetreehaveanillnessthatstuntstheirgrowthc. Theleavesofthetreearenonfunctional.d. Theleavesofthetreeareintroducedtoreducewaterloss.

8. Anuclearpowerplanthasrecentlybeenbuilttogenerateelectricityforatownlocatednearseveralsmalllakes.Whichisnotabenefitofthisnuclearplantbeingbuilt?

a. Thecostoftheelectricitywilldecrease.b. Thelossofhabitatforlocalwildlife.c. Theheatingofhomeswillbeeasier.d. Thenuclearpowerplantwillprovidejobs.

Unit7Exam 6

9. Chipmunksarelittlerodentsthatliveintheforest.Thegraphbelowillustrateshowachipmunkpopulationchangedovertime.

Whichmostlikelyhappenedin2009?

a. Anillnesshitthechipmunkpopulation.b. Therewasanincreasedfoodsourceforthechipmunks.c. Anillnesshitthechipmunk’spredatorpopulation.d. Thechipmunkpopulationevolvedovertime.

Unit7Exam 7

10. Acrosssectionofrocklayersisshownbelow.

Whichfossilisfoundintheoldestlayer?

a. Dinosaurb. Fishc. Shelld. Leaf

11. WhichstatementdescribesapossibleconsequenceifbiodiversityweretodecreaseintheArcticduetotheextinctionofpolarbears?

a. Changesinthefoodweb,leadingtoalossoffoodresourcesfornativepeopleb. Anincreaseinthenumberofproducersafteraherbivorepopulationboomc. Adecreaseinthenumberofherbivoresduetonaturalpredatorsbeinggone.d. Disturbancesinweatherpatterns,leadingtoahigheraveragewatertemperature

Unit7Exam 8

12. Whichadaptationofblackbearsbesthelpsthemsurvivecoldwinters?a. Havingalargehomerangeb. Beingabletohibernatec. Eatingbothplantsandanimalsd. Havingsharpteethandclaws

13. Anorganismandaclassificationkeyareshownbelow

Basedonthekey,whatorganismisshown?

a. Earthwormb. Centipedec. Waterpennyd. Horseshoecrab

Unit7Exam 9

14. Thepicturebelowshowsmalestagbeetlesthathavedifferentmandibletypes.

Malebeetleswithlargemandiblesarebestatguardingburrowswherefemaleshavelaideggs.Maleswhosemandiblesareabsentarebestatdiggingalternateentrancestoaguardedburrowtoreachfemales.Thetablebelowshowsthenumberofmalestagbeetleswithdifferentmandibletypesinonepopulation.

Basedonthisinformation,whichtwomandibletypeswillprobablybecomelesscommoninthispopulationovertime?

a. AbsentandSmallb. AbsentandMediumc. LargeandMediumd. SmallandMedium

Unit7Exam 10

15. Thegraphbelowillustratesthechangeinturtlepopulation.

WhichmostlikelyoccurredbetweenNovemberandFebruary?

a. Therewasadecreaseinthepredatorpopulation.b. Therewasadecreaseinavailablefood.c. Therewasanillnessintheturtlepopulation.d. Therewasanaturaldisaster.

16. Ascientistwasdiggingforfossilsalongarockycliff.Thescientistdiscoveredtrilobitefossilsinrocksattwodifferentdepthsinthecliff.Whatcanbedeterminedaboutthefossilsbasedontheirlocations?

a. Therelativeageofthetrilobitefossilsb. Thedietofthetrilobitesc. Thenumberoftrilobitepredatorsd. Thesizeoftrilobitepopulation

17. Manypeopledependonfoodcaughtintheocean.Whichactionbesthelpspeoplemaintaintheoceansasafoodsource?

a. Addinggardenfertilizerstooceansb. Exploringnewpartsofoceansc. Preventingalossofbiodiversityinoceansd. Buildingmoresportfishingareasnearoceans

Unit7Exam 11

18. Twogeologicalcolumnsareshownbelow.Thecolumnsarefromareasabout1kilometerapart.

Whichlayersweremostlikelydepositedatthesametime?

a. Layers1and4b. Layers2and3c. Layers3and4d. Layers2and6

Unit7Exam 12

19. Afishandadichotomouskeyareshownbelow.

Accordingtothedichotomouskey,whichfishispictured?

a. Smallmouthbassb. Yellowperchc. Gobyd. Lanternfish

Unit7Exam 13

20. Amuskoxisalarge,heavymammal.Ithasshortlegsandiscoveredinlong,thickhair.Amuskoxis

showninthepicturebelow.

Basedonitscharacteristics,inwhichenvironmentisapopulationofmuskoxbestsuitedtolive?

a. Tundrab. Desertc. Wetlandd. Rainforest

21. Whichpopulationwouldbestbeadaptedtomaneuverinarocky,mountainousregion?a. Apopulationoforganismswithhoovesb. Apopulationoforganismswiththickfurc. Apopulationoforganismswithgillsd. APopulationoforganismswithmoistskin

Unit7Exam 14

22. Thegraphbelowillustratesthegrowthofarabbitpopulation.

Whichmostlikelyoccurredbetween1987and1988?

a. Therewasadecreaseintheavailableamountoffood.b. Therewasanincreaseincompetition.c. Therewasadecreaseinthepredatorpopulation.d. Therewasanillnessamongthepopulation.

23. Fertilizerscontainingphosphorousandnitrogenareleachedintoapond.Thenutrientsfromthefertilizercausealgaecoloniesinthepondtogrowrapidly.Aslargequantitiesofalgaedie,thepondwaterbecomesdepletedofoxygen.Whatwillmostlikelyhappentothepondnext?

a. Agreaternumberoforganismswillloveinthepond.b. Therewillbelessbiodiversityinthepond.c. Thewaterwillbecomemoreclear.d. Thedepthofthepondwillincrease.

Unit7Exam 15

24. Thediagrambelowshowsthreesubstratelayerswithfossils.

Whichstatementisbestsupportedbythediagram?

a. ThefossilinLayer1isolderthanthefossilinLayer2.b. ThefossilinLayer3isolderthanthefossilinLayer2.c. ThefossilsinLayers2and3arefromcloselyrelatedorganisms.d. ThefossilsinLayers1and3arefromcloselyrelatedorganisms.

Unit7Exam 16

25. Anorganismliketheoneshowninthepicturebelowiscaughtinanet.

Usingtheclassificationkeyabove,identifytheorganism’sclass.

a. ClassInsectab. ClassReptiliac. ClassMammaliad. ClassChondrichthes