Week 2 Blanked

120:Dr. Schmidt BICD 1A ZaraTabi(ztabi@ucsd,edu) Week2 AIM:ztabi06 Details TheNitty-Gritty Photosynthesis: + 60z + 12NADP*+18ADP+ 6 HzO 6COz+ 12HzO+12NADPH+ 18ATP) CoHrzOo fromlightenergy!

and Production of TheLiqhtReactions: inPhotosynthesis Pigments - lmportant . Primary pigment; photosynthetic . Secondary/Accessory Help Pigments; inthe ) located

) located inthereaction center ofeachphotosystem byplant spectrum of lightthatcanbeabsorbed (LHC)orAntenna Complex

. Beableto interpret graphs andActionSpectra! oftheAbsorption experiment from whatwasconcluded T.W.Engleman's - Understand unit= -Photosynthetic . Sizeof LHChelpsprevent

oflightabsorbed bycontrolling theamount photooxidation forms cell-damaging which isthecauseof

. Growing in . Growing in

toprevent damage abletogatherfreeradicals morelightenergy sizeof LHCtoabsorb chlorophyll BIARatio lightintake sizeof LHCtoregulate chlorophyll B/Aratio

) ) ) )

complex: ofeachprotein - Knowthenameandlocation

th t

6trorna-

ligvtt

NADP}T

ztl+

?\r-,Pf'notto

vi

2$+

9*o'

[r PlooaY'wiru-

Photophosphorylation Vs.Noncyclic - Cyclic . lnNon-Cyclic photophosphorylation: ll andI Photosystem - UseofBOTH Oz,afld NADPH of 2HzOproduces e-,- Splitting viaphotophosphorylation ATPproduced lumenper2HzO) _ intothylakoid H*pumped photosystem per quanta each oflighttotaltomove4 e-) -

backto . InCyclicphotophosphorylation, soe-areshuttled tobereduced, isavailable no topumpmoreH+) MoreATPProduced issplit ) NoHzO onlyPhotosystem - Uses foodsource fromCOzFixation Producing PhotosvnthesisCvcle/DarkReactions/C3 TheCatvin by - Discovered - COzinitiallyfixedintoa 3-Cmolecule(

@co'

0sbisco - o

GCin+efinediate

@ ribulo$obiph ospvratu

\

3rc0<-f- feuor;

q r' 'rP DA-

@) O-piorpl,ogrScrrcre-

a#toororrADPll O GOP

).^

aN+

';lHil],5; a,4 ,?, 1#:,s,a,,che ffi "

NADPH ATPand - Need PerCO2Fixed andforBOTH ) hasanaffinity withRubisco - TheProblem to binds Rubisco COz]= Ozland t '[ . L-Ozland to binds Rubisco COzl= t

HatchandSlack(1965) byscientists fixation, discovered method ofcarbon C4Photosynthesis-Another instead of3-C! ( - WhyCalledC4?) COzFixedendsupina 4-Cmolecule are - C4andC3photosynthesis

C.,$t --*llrCo3 llzD

PTP

(Ltc) NA,DP+NAppt{

n4alate +!-

O,tn

v\alqYg

P!r uv aw4

Cetts - ctt ilesoghgtl

,/

-Whydoit whenit usesupmoreenergy (intheformof highenergyphosphates, whenATp) AMp)? . Makes a PROCESS: 1) hasa higheraffinity forCOzincomparison to 2)Create anenvironment of tofavorCO2fixation overphotorespiration 3)Arrangement ofcells(C4or KranzAnatomy) helps thatmay havebeenlostduring photorespiration - Because CO2loss is

. ldealforplantsthatliveinareasof high

stomata moreoften) lessH2Oloss! and

where rateofphotorespiration increases ex.TropicalGrasses-Maize, Sugar Cane, Millet, etc. CAM(Cfas$ulacean AcidMetabolisml PhotosvnthesisAnalternate version ofC4photosynthesis - C4andC3Reactions are_ separated-Day andNiqht

Cot +

Hrco,

Fzo

ATP

- Because high[] of - Whydiditevolve?

(malicacid)storedinthevacuole atnight,pHwillusually be

. Helpplantsthatlivein locations withlittle - Keepstomata duringthedaytime toprevent waterloss ) Canstillperform C3photosynthesis stomata atnightwhentemperature iscoolertotakeinco2 toperform c4 photosynthesis . ex.Cacti, pinepple succulents,

Primary Productivitv, GlobalWarminqQuestions tothinkabout: - Definition productivity? forprimary - Whattypesofplants(C3,C4,CAM,etc.)arethemostefficient atfixingCO2?Leastefficient? - Whatcontinental playsanimportant ecosystem roleinfixing themosttarbonperyear? - HowmanyPounds ofCO2arereleased gallon forevery ofgasused? (Refer tothehandout given on10/08/09 lecture!)