BIOLl 1108l Examl 2l l Principlesl ofl

BIOLl 1108l Examl 2l –l Principlesl ofl Biologyl IIl (Latestl 2026/l 2027l Update)l Review|l 100%l Verifiedl Questionsl &l Answersl |l Gradel A

Q:l leafl anatomy:l epidermis

Answer:

sheetsl ofl cellsl thatl linel thel leaf'sl upperl andl lowerl surfaces

Q:l leafl anatomy:l mesophyll

Answer:

looselyl packedl photosyntheticl cells

Q:l leafl anatomy:l veins

Answer:

vascularl conduitl unitl thatl connectsl leafl tol restl ofl thel plant

Q:l functionl ofl leaf

Answer:

allowsl gasl exchange,l photosynthesisl andl transpiration

Q:l whyl doesl CO2l uptakel resultl inl waterl loss?

Answer: 1 / 4

whenl stomatal open,l waterl vaporl escapesl (waterl vaporl moleculesl diffusel intol areasl ofl lowerl concentration)

Q:l transpiration

Answer:

lossl ofl waterl vaporl froml leaves

Q:l stomata

Answer:

poresl inl epidermisl thatl allowsl CO2l tol diffuse intol thel leaf;l consistsl ofl twol guardl cellsl surroundingl al centrall pore;l guardl cellsl canl shrinkl orl swelll controllingl opening

Q:l CAMl plantsl (photosynthesisl adaptation)

Answer:

CAMl photosynthesis;l usel nocturnall CO2l storagel tol avoidl waterl lossl duringl thel dayl forl plantsl whol livel inl aridl climates

Q:l C4l plantsl (photosynthesisl adaptation)

Answer:

suppressl photorespirationl byl increasingl thel concentrationl ofl CO2l inl thel immediatel vicinityl ofl rubisco -dol thisl byl initiallyl capturingl CO2l inl mesophylll cellsl byl meansl ofl PEPl carboxylasel whichl producesl al 4-carbonl organicl acidl thatl diffusel throughl plasmodesmstsl intol bundlel sheaths -oncel inside,l 4-carbonl compoundsl arel decarboxylated,l releasingl CO2 -cyclel isl completedl asl al 3-carbonl moleculel diffusesl backl intol mesophylll cells -operatesl fasterl thanl calvinl cycle

-includes:l pineapple,l corn,l sugarcane,l wheat

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Q:l parenchyma

Answer:

undifferentiated,l thin-walledl cellsl inl thel interior;l composel mostl ofl interior

Q:l phloem

Answer:

differentiatedl vascularl tissue;l betweenl xyleml andl vascualrl bundle;l transportsl carbohydratesl froml leavesl tol thel restl ofl thel plantl body

Q:l xylem

Answer:

differentiatedl DEADl vascularl tissue;l onl thel interior,l transportsl waterl froml rootsl tol thel leaves

Q:l treacheryl elements

Answer:

partl ofl xylem:l tracheidsl andl vessell elements

Q:l tracheids

Answer:

xylem:l dead,l long,l narrowl cellsl bearingl pitsl onl sidel wallsl andl endl wall

Q:l vessell elements

Answer: 3 / 4

xylem:l deadl cellsl withl openl endl wallsl (nol pitl membranel remains)l calledl perforatedl plates;l shorterel andl widerl thanl tracheids

Q:l waterl flowl inl xylem

Answer:

pulledl byl evaporativel pump -whenl stomatal openl waterl evaporatesl froml wallsl ofl cellsl liningl intercellularl airl spacel ofl leaves -partiall dehydrationl pullsl waterl evaporatesl towardsl sitesl ofl evaporationl similarl tol al spongel (pulledl byl cohesion)

Q:l riskl ofl xyleml conduits

Answer:

1.l collapse:l shrinkagel ofl xylem;l tol printl this,l xyleml isl thickenedl withl wallsl ofl lignin 2.l cavitation:l abruptl replacementl ofl waterl byl waterl vapor;l disruptsl continuationl ofl thel waterl columnl (twol ways) -airl bubblel pulledl throughl pitl duel tol lowerl pressurel inl waterl vsl air -gasesl comingl outl ofl solutionl duringl freezing solution:l xyleml consistsl ofl manyl conduitsl inl parallel,l lossl ofl onel isl notl detrimental

Q:l sievel tubel membersl (STM)

Answer:

phloem:l (inl angiosperms)l wherel sugarl transportl occurs;l connectedl byl sievel plats

Q:l companionl cells

Answer:

phloem:l (inl angiosperms)l wherel cellularl functionl suchl asl proteinl synthesisl occurs

Q:l sourcel tol sink

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