Biology 20 Review Exam Questions and
Answers
Dynamic iiequilibrium ii- iiAnswers ii-Constant iichange iiwithin iian iiecosystem iiin iiwhich iithe
iicomponents iican iiadjust iito iithe iichanges iiwithout iidisturbing iithe iiecosystem
Biosphere ii- iiAnswers ii-The iinarrow iizone iiaround iiearth iithat iiharbours iilife
What iiis iithe iibiosphere iicomposed iiof? ii- iiAnswers ii-The iilithosphere, iihydrosphere,
iiand iiatmosphere
Biotic ii- iiAnswers ii-Living iicomponents iiof iian iiecosystem
Abiotic ii- iiAnswers ii-Non-living iicomponents iiof iian iiecosystem
Order iithese: iitissues, iisystems, iicells, iiorgans ii- iiAnswers ii-Cells, iitissues, iiorgans,
iisystems
Population ii- iiAnswers ii-A iigroup iiof iithe iisame iispecies
Community ii- iiAnswers ii-A iigroup iiof iipopulations
Ecosystem ii- iiAnswers ii-A iigroup iiof iipopulations iiwith iiabiotic iifactors
Food iichain ii- iiAnswers ii-A iistep-by-step iisequence iilinking iiorganisms iithat iifeed iion
iieach iiother
Producer ii- iiAnswers ii-An iiautotroph iithat iimakes iiits iiown iifoot
Consumer ii- iiAnswers ii-A iiheterotroph iithat iieats iiproducers iiand iiother iiconsumers
Indicator iispecies ii- iiAnswers ii-A iispecies iisensitive iito iismall iichanges iiin iienvironmental
iiconditions
Herbivore ii- iiAnswers ii-An iianimal iithat iieats iionly iiplants
Carnivore ii- iiAnswers ii-Only iieats iimeat
Omnivore ii- iiAnswers ii-Eats iiboth iiplants iiand iianimals
,Explain iithe iicircumstance iiin iiBangladesh iiwhere iifrogs iiwere iiover-hunted ii- iiAnswers ii-
Frog iipopulations iifell, iiinsect iipopulations iisoared, iiamong iithem iimosquitoes,
iiincreasing iithe iicases iiof iimalaria
Detritus ii- iiAnswers ii-The iiwaste iifrom iiplants iiand iianimals iiincluding iitheir iidead
iiremains
Decomposer ii- iiAnswers ii-An iiorganism iithat iibreaks iidown iidetritus
Why iiare iiindicator iispecies iiimportant? ii- iiAnswers ii-Because iithey iialert iiobservers iiof
iichanges ii(oftentimes iinegative) iiin iithe iiecosystem
Habitat ii- iiAnswers ii-The iiplace/environment iiwith iiconditions iisuitable iifor iithe iisurvival
iiof iian iiindividual, iior iipopulation iiof iian iiorganism
What iiis iithe iimain iicause iifor iihe iidecline iiin iipopulation iiof iifrogs? ii- iiAnswers ii-Habitat
iiloss
What iiare iithe iifour iimajor iicauses iiof iifrog iipopulation iidecline? ii- iiAnswers ii-Habitat
iiloss, iiAir iiand iiwater iiquality, iiclimate iichange, iiand iiUV iiradiation
How iidoes iiair iiand iiwater iiquality iiaffect iithe iifrog iipopulation? ii- iiAnswers ii-Frogs
iibreathe iithrough iitheir iiskin, iiso iipollution iigets iiinto iitheir iisystem. iiAcidic iiconditions
iilessen iithe iichances iiof iian iiegg iibeing iifertilized iibecause iiit iidecreases iithe iimovement
iiof iisperm, iiand iicause iimutations iiin iithe iitadpoles
How iidoes iiclimate iichange iiaffect iithe iifrog iipopulation? ii- iiAnswers ii-Frogs iican't
iiseparate iithemselves iifrom iiwater iifor iitoo iilong, iiso iiif iiponds iistart iito iidry iiout, iithe
iipopulation iideclines
How iidoes iiUV iiradiation iiaffect iifrog iipopulation? ii- iiAnswers ii-The iithinning iiof iithe
iiO3(g) iilayer iicauses iimore iiUV iiradiation iito iipass iithrough. iiThis iiharms iithe iisensitive
iiskin iiof iithe iifrog ii(which iialso iilive iiat iihigher iialtitudes) iiand iidamages iitheir iicells.
iiEspecially iithose iiwith iiblack iieggs.
Explain iithe iiGaia iiHypothesis ii- iiAnswers ii-Emphasizes iithat iiall iiliving iithings iiinteract
iiwith iieach iiother iiand iithe iinon-living iicomponents iiof iiour iiplanet
Is iia iivirus iibiotic iior iiabiotic? ii- iiAnswers ii-Abiotic
True iior iiFalse:
All iicomponents iiof iithe iibiosphere iiinteract iiwith iiboth iibiotic iiand iiabiotic iifactors ii-
iiAnswers ii-True
Extirpation ii- iiAnswers ii-When iian iianimal iiis iiextinct iifrom iia iicertain iiarea
,Endangered ii- iiAnswers ii-A iispecies iiclose iito iiextinction
Explain iithe iidecline iiin iieagle iipopulation ii- iiAnswers ii-Their iieggshells iiwere iibecoming
iithinner iidue iito iichemicals iibeing iiintroduced iiinto iitheir iifood iichain
Threatened iispecies ii- iiAnswers ii-A iispecies iithat iiis iilikely iito iibecome iiendangered
Special iiconcern iispecies ii- iiAnswers ii-A iispecies iiat iirisk iibecause iiof iilow iior iideclining
iinumbers
Top iilevel iiconsumer ii- iiAnswers ii-They iihave iino iipredator iibut iiact iias iia iipredator iito
iiall
Examples iiof iiendangered, iiextirpated, iithreatened, iiand iispecial iiconcern iispecies ii-
iiAnswers ii-Whooping iicrane iiin iiAlberta, iiGrizzly iiBears iiin iiMexico, iiFowler's iiToad iiand
iiLeopard iifrogs iiin iiOntario, iiWolverines iiin iiNunavut
What iiis iithe iidifference iibetween iia iiproducer iiand iia iidetritus iifood iichain? ii- iiAnswers ii-
Producer: iiwhere iithe iiconsumers iifeed iidirectly iior iiindirectly iion iithe iiproducer
Detritus: iiwhere iiwaste iiis iirecycled iithroughout iiand iithere iiare iitwo iisources ii(producers
iiand iiwaste)
Why iido iidecomposers iibreak iidown iidetritus? ii- iiAnswers ii-To iirecycle iithe iinutrients
What iifactors iidetermine iibiodiversity? ii- iiAnswers ii-The iiamount iiof iienergy, iiand iiwater
iiavailable
Biome ii- iiAnswers ii-A iicommunity iiof iiecosystems
Bioaccumulation ii- iiAnswers ii-Increased iiconcentration iiof iitoxins iiin iihigher iilevels iiof
iithe iifood iichain ii(AKA iibiomagnification)
What iiis iithe iidifference iibetween iithe iitop-down iieffect iiand iithe iibottom-up iieffect? ii-
iiAnswers ii-Top-down: iitop iiconsumer iideclines, iiits iiprey iiincreases, iicausing iiITS iiprey
iito iidecrease, iiand iiso iion
Bottom-up: iiproducer iideclines, iiall iiconsumers iidecline iias iiwell
Chemosynthesis ii- iiAnswers ii-Splitting iian iiinorganic iichemical iisubstance iisuch iiad
iiH2S(s) iiinto iiH2SO4(aq) iito iiharness iithe iienergy
Examples iiof iichemosynthetic iiproducers ii- iiAnswers ii-Autotrophs iiin iivolcanic iideep-sea
iivents
, Autotroph ii- iiAnswers ii-Makes iiits iiown iifood iiat iithe iifirst iitrophic iilevel
Heterotroph ii- iiAnswers ii-Obtains iifood iifrom iiother iiliving iiorganisms
Food iiweb ii- iiAnswers ii-Interlinking iifood iichains
What iido iithe iiarrows iiin iia iifood iichain iiand iia iifood iiweb iisignify? ii- iiAnswers ii-The iiflow
iiof iienergy
What iiis iithe iidifference iibetween iia iifood iichain iiand iia iifood iiweb? ii- iiAnswers ii-When
iiin iia iifood iichain, iione iican iibe iiin iionly iiONE iitrophic iilevel iiat iia iitime. iiIn iia iifood iiweb,
iione iican iibe iiin iimore iithan iione iitrophic iilevel iiat iia iitime ii(eat iiboth iiproducers iiand
iiconsumers)
What iiare iithe iilaws iiof iithermodynamics? ii- iiAnswers ii-1. iiEnergy iican't iibe iicreated iior
iidestroyed
2. iiIn iievery iienergy iiconversion, iithere iiis iiheat iilost
How iimuch iienergy iiis iipassed iifrom iione iitrophic iilevel iito iianother? ii- iiAnswers ii-10%
What iiis iithe iienergy iiretained iiin iiproducers iiand iiconsumers iiused iifor? ii- iiAnswers ii-
70% iiis iifor iibodily iifunctions iiand iilost iias iiheat.
The iiremaining ii20% iiremains iiin iithe iibody
How iimuch iiof iithe iisun's iienergy iido iiplants iiget? ii- iiAnswers ii-1%
What iihappens iito iithe iienergy iiof iithe iisun iinot iitaken iiby iiplants? ii- iiAnswers ii-It iiis
iireflected/absorbed iielsewhere
If iithe iisun iipasses ii1,000,000kJ iiof iienergy iito iia iiplant, iihow iimuch iidoes iithe iitertiary
iiconsumer iiget? ii- iiAnswers ii-Plant: ii10,000kJ
Primary iiconsumer: ii1000kJ
Secondary iiconsumer: ii100kJ
Tertiary iiconsumer: ii10kJ
How iidoes iiit iimake iisense iithat ii20% iiof iienergy iiregardless iiof iiwhere iithey iiare iiin iithe
iifood iichain iigoes iito iithe iidecomposers? ii- iiAnswers ii-That's iithe iiamount iiretained iiin
iithe iibody iiof iithe iiconsumer/producer iiwhen iiit iidies
Ecological iipyramids ii- iiAnswers ii-Diagrams iiused iito iishow iiquantitative iirelationships
iibetween iitrophic iilevels
Answers
Dynamic iiequilibrium ii- iiAnswers ii-Constant iichange iiwithin iian iiecosystem iiin iiwhich iithe
iicomponents iican iiadjust iito iithe iichanges iiwithout iidisturbing iithe iiecosystem
Biosphere ii- iiAnswers ii-The iinarrow iizone iiaround iiearth iithat iiharbours iilife
What iiis iithe iibiosphere iicomposed iiof? ii- iiAnswers ii-The iilithosphere, iihydrosphere,
iiand iiatmosphere
Biotic ii- iiAnswers ii-Living iicomponents iiof iian iiecosystem
Abiotic ii- iiAnswers ii-Non-living iicomponents iiof iian iiecosystem
Order iithese: iitissues, iisystems, iicells, iiorgans ii- iiAnswers ii-Cells, iitissues, iiorgans,
iisystems
Population ii- iiAnswers ii-A iigroup iiof iithe iisame iispecies
Community ii- iiAnswers ii-A iigroup iiof iipopulations
Ecosystem ii- iiAnswers ii-A iigroup iiof iipopulations iiwith iiabiotic iifactors
Food iichain ii- iiAnswers ii-A iistep-by-step iisequence iilinking iiorganisms iithat iifeed iion
iieach iiother
Producer ii- iiAnswers ii-An iiautotroph iithat iimakes iiits iiown iifoot
Consumer ii- iiAnswers ii-A iiheterotroph iithat iieats iiproducers iiand iiother iiconsumers
Indicator iispecies ii- iiAnswers ii-A iispecies iisensitive iito iismall iichanges iiin iienvironmental
iiconditions
Herbivore ii- iiAnswers ii-An iianimal iithat iieats iionly iiplants
Carnivore ii- iiAnswers ii-Only iieats iimeat
Omnivore ii- iiAnswers ii-Eats iiboth iiplants iiand iianimals
,Explain iithe iicircumstance iiin iiBangladesh iiwhere iifrogs iiwere iiover-hunted ii- iiAnswers ii-
Frog iipopulations iifell, iiinsect iipopulations iisoared, iiamong iithem iimosquitoes,
iiincreasing iithe iicases iiof iimalaria
Detritus ii- iiAnswers ii-The iiwaste iifrom iiplants iiand iianimals iiincluding iitheir iidead
iiremains
Decomposer ii- iiAnswers ii-An iiorganism iithat iibreaks iidown iidetritus
Why iiare iiindicator iispecies iiimportant? ii- iiAnswers ii-Because iithey iialert iiobservers iiof
iichanges ii(oftentimes iinegative) iiin iithe iiecosystem
Habitat ii- iiAnswers ii-The iiplace/environment iiwith iiconditions iisuitable iifor iithe iisurvival
iiof iian iiindividual, iior iipopulation iiof iian iiorganism
What iiis iithe iimain iicause iifor iihe iidecline iiin iipopulation iiof iifrogs? ii- iiAnswers ii-Habitat
iiloss
What iiare iithe iifour iimajor iicauses iiof iifrog iipopulation iidecline? ii- iiAnswers ii-Habitat
iiloss, iiAir iiand iiwater iiquality, iiclimate iichange, iiand iiUV iiradiation
How iidoes iiair iiand iiwater iiquality iiaffect iithe iifrog iipopulation? ii- iiAnswers ii-Frogs
iibreathe iithrough iitheir iiskin, iiso iipollution iigets iiinto iitheir iisystem. iiAcidic iiconditions
iilessen iithe iichances iiof iian iiegg iibeing iifertilized iibecause iiit iidecreases iithe iimovement
iiof iisperm, iiand iicause iimutations iiin iithe iitadpoles
How iidoes iiclimate iichange iiaffect iithe iifrog iipopulation? ii- iiAnswers ii-Frogs iican't
iiseparate iithemselves iifrom iiwater iifor iitoo iilong, iiso iiif iiponds iistart iito iidry iiout, iithe
iipopulation iideclines
How iidoes iiUV iiradiation iiaffect iifrog iipopulation? ii- iiAnswers ii-The iithinning iiof iithe
iiO3(g) iilayer iicauses iimore iiUV iiradiation iito iipass iithrough. iiThis iiharms iithe iisensitive
iiskin iiof iithe iifrog ii(which iialso iilive iiat iihigher iialtitudes) iiand iidamages iitheir iicells.
iiEspecially iithose iiwith iiblack iieggs.
Explain iithe iiGaia iiHypothesis ii- iiAnswers ii-Emphasizes iithat iiall iiliving iithings iiinteract
iiwith iieach iiother iiand iithe iinon-living iicomponents iiof iiour iiplanet
Is iia iivirus iibiotic iior iiabiotic? ii- iiAnswers ii-Abiotic
True iior iiFalse:
All iicomponents iiof iithe iibiosphere iiinteract iiwith iiboth iibiotic iiand iiabiotic iifactors ii-
iiAnswers ii-True
Extirpation ii- iiAnswers ii-When iian iianimal iiis iiextinct iifrom iia iicertain iiarea
,Endangered ii- iiAnswers ii-A iispecies iiclose iito iiextinction
Explain iithe iidecline iiin iieagle iipopulation ii- iiAnswers ii-Their iieggshells iiwere iibecoming
iithinner iidue iito iichemicals iibeing iiintroduced iiinto iitheir iifood iichain
Threatened iispecies ii- iiAnswers ii-A iispecies iithat iiis iilikely iito iibecome iiendangered
Special iiconcern iispecies ii- iiAnswers ii-A iispecies iiat iirisk iibecause iiof iilow iior iideclining
iinumbers
Top iilevel iiconsumer ii- iiAnswers ii-They iihave iino iipredator iibut iiact iias iia iipredator iito
iiall
Examples iiof iiendangered, iiextirpated, iithreatened, iiand iispecial iiconcern iispecies ii-
iiAnswers ii-Whooping iicrane iiin iiAlberta, iiGrizzly iiBears iiin iiMexico, iiFowler's iiToad iiand
iiLeopard iifrogs iiin iiOntario, iiWolverines iiin iiNunavut
What iiis iithe iidifference iibetween iia iiproducer iiand iia iidetritus iifood iichain? ii- iiAnswers ii-
Producer: iiwhere iithe iiconsumers iifeed iidirectly iior iiindirectly iion iithe iiproducer
Detritus: iiwhere iiwaste iiis iirecycled iithroughout iiand iithere iiare iitwo iisources ii(producers
iiand iiwaste)
Why iido iidecomposers iibreak iidown iidetritus? ii- iiAnswers ii-To iirecycle iithe iinutrients
What iifactors iidetermine iibiodiversity? ii- iiAnswers ii-The iiamount iiof iienergy, iiand iiwater
iiavailable
Biome ii- iiAnswers ii-A iicommunity iiof iiecosystems
Bioaccumulation ii- iiAnswers ii-Increased iiconcentration iiof iitoxins iiin iihigher iilevels iiof
iithe iifood iichain ii(AKA iibiomagnification)
What iiis iithe iidifference iibetween iithe iitop-down iieffect iiand iithe iibottom-up iieffect? ii-
iiAnswers ii-Top-down: iitop iiconsumer iideclines, iiits iiprey iiincreases, iicausing iiITS iiprey
iito iidecrease, iiand iiso iion
Bottom-up: iiproducer iideclines, iiall iiconsumers iidecline iias iiwell
Chemosynthesis ii- iiAnswers ii-Splitting iian iiinorganic iichemical iisubstance iisuch iiad
iiH2S(s) iiinto iiH2SO4(aq) iito iiharness iithe iienergy
Examples iiof iichemosynthetic iiproducers ii- iiAnswers ii-Autotrophs iiin iivolcanic iideep-sea
iivents
, Autotroph ii- iiAnswers ii-Makes iiits iiown iifood iiat iithe iifirst iitrophic iilevel
Heterotroph ii- iiAnswers ii-Obtains iifood iifrom iiother iiliving iiorganisms
Food iiweb ii- iiAnswers ii-Interlinking iifood iichains
What iido iithe iiarrows iiin iia iifood iichain iiand iia iifood iiweb iisignify? ii- iiAnswers ii-The iiflow
iiof iienergy
What iiis iithe iidifference iibetween iia iifood iichain iiand iia iifood iiweb? ii- iiAnswers ii-When
iiin iia iifood iichain, iione iican iibe iiin iionly iiONE iitrophic iilevel iiat iia iitime. iiIn iia iifood iiweb,
iione iican iibe iiin iimore iithan iione iitrophic iilevel iiat iia iitime ii(eat iiboth iiproducers iiand
iiconsumers)
What iiare iithe iilaws iiof iithermodynamics? ii- iiAnswers ii-1. iiEnergy iican't iibe iicreated iior
iidestroyed
2. iiIn iievery iienergy iiconversion, iithere iiis iiheat iilost
How iimuch iienergy iiis iipassed iifrom iione iitrophic iilevel iito iianother? ii- iiAnswers ii-10%
What iiis iithe iienergy iiretained iiin iiproducers iiand iiconsumers iiused iifor? ii- iiAnswers ii-
70% iiis iifor iibodily iifunctions iiand iilost iias iiheat.
The iiremaining ii20% iiremains iiin iithe iibody
How iimuch iiof iithe iisun's iienergy iido iiplants iiget? ii- iiAnswers ii-1%
What iihappens iito iithe iienergy iiof iithe iisun iinot iitaken iiby iiplants? ii- iiAnswers ii-It iiis
iireflected/absorbed iielsewhere
If iithe iisun iipasses ii1,000,000kJ iiof iienergy iito iia iiplant, iihow iimuch iidoes iithe iitertiary
iiconsumer iiget? ii- iiAnswers ii-Plant: ii10,000kJ
Primary iiconsumer: ii1000kJ
Secondary iiconsumer: ii100kJ
Tertiary iiconsumer: ii10kJ
How iidoes iiit iimake iisense iithat ii20% iiof iienergy iiregardless iiof iiwhere iithey iiare iiin iithe
iifood iichain iigoes iito iithe iidecomposers? ii- iiAnswers ii-That's iithe iiamount iiretained iiin
iithe iibody iiof iithe iiconsumer/producer iiwhen iiit iidies
Ecological iipyramids ii- iiAnswers ii-Diagrams iiused iito iishow iiquantitative iirelationships
iibetween iitrophic iilevels
