AP Notes on Cell Resp and Photosynthesis

7/17/2019 AP Notes on Cell Resp and Photosynthesis

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UNIT 3 – PHOTOSYNTHESIS AND CELLULARRESPIRATION

CELL SIGNALING

IN THIS UNIT, STUDENTS WILL LEARN ABOUT THE IMPORTANCE,LOCATION AND THE VARIOUS PROCESSES OF CELLULARRESPIRATION AND PHOTOSYNTHESIS. BY THE END OF THEUNIT, THEY MUST BE ABLE TO INDEPENDENTLY DESCRIBE THESTEPS OF EACH PROCESS, WHY THEY ARE SO IMPORTANT INTHE ECOSYSTEM, THEIR LOCATIONS AND WHAT CONDITIONSARE NECESSARY FOR EACH. THIS IS A VERY DEMANDING UNITWITH VERY COMPLEX CHEMICAL PROCESSES. A GOOD DEEPKNOWLEDGE OF CHEMISTRY IS CRUTIAL.WE WILL USE TWO LABS, VARIOUS IMAGES, ACTIVITIES ANDTWO CONCEPT MAPS TO OBTAIN A DEEPER AND MORE

THOUROUGH UNDERSTANDING OF THIS UNIT.Case stu!"#tt$"%%&&&.s'(e)'e'ases.*+%+(*+-*+t(s%+(*+-*+t(s.as$ /+e0(e& us'1e '*)t+a't(*) *)#tt$"%%e)t*'#e.tau.eu%Mus'1eSt+u'C*)t+a'ts&2%()e3.#t1 4G+eat a)(at(*) 2+* 1ea2 st+u'tu+e t* $#*t*s!)t#es(s"#tt$"%%e)+*.')+e.0t.eu%2*+est5(*1*!%$#*t*s!)t#es(s.s&2

CHAPTER 6 7 CELLULAR RESPIRATION

OB8ECTIVE 9UESTIONST#e P+()'($1es *2 E)e+! Ha+0est

1. In general terms, !st!ng"!s# $et%een &ermentat!'n an (ell"larres)!rat!'n.

*. +r!te t#e s"mmar e-"at!'n &'r (ell"lar res)!rat!'n. +r!te t#es)e(!( (#em!(al e-"at!'n &'r t#e egraat!'n '& gl"('se.

3. Dene '/!at!'n an re"(t!'n.0. E/)la!n !n general terms #'% re'/ rea(t!'ns are !n'le !n

energ e/(#anges.2. Des(r!$e t#e r'le '& NAD !n (ell"lar res)!rat!'n.4. In general terms, e/)la!n t#e r'le '& t#e ele(tr'n trans)'rt (#a!n

!n (ell"lar res)!rat!'n.

T#e P+*'ess *2 Ce11u1a+ Res$(+at(*)5. Name t#e t#ree stages '& (ell"lar res)!rat!'n an state t#e reg!'n

'& t#e e"6ar't!( (ell %#ere ea(# stage '(("rs.7. Des(r!$e #'% t#e (ar$'n s6elet'n '& gl"('se (#anges as !t

)r'(ees t#r'"g# gl('ls!s.

http://www.sciencecases.org/rigor_mortis/rigor_mortis.asp

http://entochem.tamu.edu/MuscleStrucContractswf/index.html

http://dendro.cnre.vt.edu/forestbiology/photosynthesis.swf

http://www.sciencecases.org/rigor_mortis/rigor_mortis.asp

http://entochem.tamu.edu/MuscleStrucContractswf/index.html

http://dendro.cnre.vt.edu/forestbiology/photosynthesis.swf



8. E/)la!n %# ATP !s re-"!re &'r t#e )re)arat'r ste)s '&gl('ls!s.

19. Ient!& %#ere s"$strate:leel )#'s)#'rlat!'n an t#ere"(t!'n '& NAD '(("r !n gl('ls!s.

11. Des(r!$e %#ere )r"ate !s '/!!;e t' a(etl C'A, %#at

m'le("les are )r'"(e, an #'% t#!s )r'(ess l!n6s gl('ls!s t't#e (!tr!( a(! ((le.1*. L!st t#e )r'"(ts '& t#e (!tr!( a(! ((le. E/)la!n %# !t !s

(alle a ((le.13. Des(r!$e t#e )'!nt at %#!(# gl"('se !s ('m)letel '/!!;e

"r!ng (ell"lar res)!rat!'n.10. D!st!ng"!s# $et%een s"$strate leel )#'s)#'rlat!'n an

'/!at!e )#'s)#'rlat!'n.12. In general terms, e/)la!n #'% t#e e/erg'n!( <sl!e= '&

ele(tr'ns '%n t#e ele(tr'n trans)'rt (#a!n !s ('")le t' t#eenerg'n!( )r'"(t!'n '& ATP $ (#em!'sm's!s.

14. E/)la!n %#ere an #'% t#e res)!rat'r ele(tr'n trans)'rt(#a!n (reates a )r't'n gra!ent.

15. Des(r!$e t#e str"(t"re an &"n(t!'n '& t#e &'"r s"$"n!ts '&ATP snt#ase.

17. S"mmar!;e t#e net ATP !el &r'm t#e '/!at!'n '& agl"('se m'le("le $ ('nstr"(t!ng an ATP leger.

18. E/)la!n %# !t !s n't )'ss!$le t' state an e/a(t n"m$er '&ATP m'le("les generate $ t#e '/!at!'n '& gl"('se.

Re1ate Meta5*1(' P+*'esses*9. State t#e $as!( &"n(t!'n '& &ermentat!'n

*1. C'm)are t#e &ate '& )r"ate !n al('#'l &ermentat!'n anla(t!( a(! &ermentat!'n.

**. C'm)are t#e )r'(esses '& &ermentat!'n an (ell"larres)!rat!'n.

*3. Des(r!$e t#e e!en(e t#at s"ggests t#at gl('ls!s !s anan(!ent meta$'l!( )at#%a.

*0. Des(r!$e #'% &'' m'le("les 't#er t#an gl"('se (an $e'/!!;e t' ma6e ATP.

*2. E/)la!n #'% gl('ls!s an t#e (!tr!( a(! ((le (an('ntr!$"te t' ana$'l!( )at#%as.

*4. E/)la!n #'% ATP )r'"(t!'n !s ('ntr'lle $ t#e (ell an

es(r!$e t#e r'le t#at t#e all'ster!( en;me )#'s)#'&r"(t'6!nase)las !n t#e )r'(ess.

I. O>ER>IE+?• L!!ng 'rgan!sms re-"!re energ &r'm '"ts!e s'"r(es t' )er&'rm

t#e!r man tas6s.



• Energ "se $ l!!ng 'rgan!sms ('mes &r'm t#e s"n an !t @'%st#r'"g# t#e e('sstem.

• >!tal elements t#at are ne(essar t' $"!l ") 'rgan!( m'le("les#'%eer, are re((le !n t#e e('sstem.

• P#'t'snt#es!s generates 'rgan!( m'le("les $ "s!ng CO*,

s"nl!g#t an '/gen. T#ese 'rgan!( m'le("les are "se !n t#em!t'(#'nr!a &'r (ell"lar res)!rat!'n t' generate ATP.

II. IPORTANT REACTIONS AND RELATED PATH+AYS OBCELLULAR RESPIRATION

A. Cata$'l!( Pat#%as• Cata5*1(' $at#&a!s 7 en;mat!( )r'(esses t#at gra"all

egrae large 'rgan!( m'le("les t#at are r!(# !n )'tent!al energt' s!m)ler %aste )r'"(ts t#at #ae less energ.

• Fe+e)tat(*) 7 a t)e '& (ata$'l!( )r'(ess, !n %#!(# t#eegraat!'n '& s"gars '(("rs %!t#'"t t#e "se '& '/gen



• Ce11u1a+ +es$(+at(*) 7 t#e m'st ('mm'n (ata$'l!( )r'(ess !n%#!(# '/gen !s ('ns"me as a rea(tant al'ng %!t# t#e 'rgan!(&"el t' &'rm large n"m$er '& ATP m'le("les?

Organ!( ('m)'"ns '/gen → CO* H*O energ

• Car$'#rates, l!)!s, an )r'te!ns are all "se t' &"el (ell"larres)!rat!'n $"t %e %!ll &'ll'% gl"('se?

C4H1*O4 4 O* → 4CO* 4 H*O energ ATP #eat

• Energ &'r %'r6 !n t#e (ell %!ll $e !re(tl )r'!e $ ATP.. Re'/ Rea(t!'ns? O/!at!'n an Re"(t!'n• In general, !n $!'l'g!(al )r'(esses t#e rel'(at!'n '& ele(tr'ns

releases energ st're !n 'rgan!( m'le("les. T#!s energ !s"lt!matel "se t' snt#es!;e ATP.

• Re*3 +ea't(*)s are (#em!(al rea(t!'ns t#at !n'le t#etrans&er '& ele(tr'ns &r'm 'ne rea(tant t' an 't#er.

• O3(at(*) 7 t#e l'ss '& ele(tr'ns, t#e s"$stan(e t#at l'st t#eele(tr'ns $e('mes *3((:e. It !s a +eu'() ae)t

• Reu't(*) 7 t#e ga!n!ng '& ele(tr'ns, t#e s"$stan(e t#at ga!net#e ele(tr'ns $e('mes +eu'e. It !s an *3((:() ae)t.

• O/!at!'n an re"(t!'n al%as ta6e )la(e t'get#er.

• Energ m"st $e ae t' )"ll an ele(tr'n a%a &r'm an at'm. T#e m're ele(tr'negat!e an at'm !s t#e m're energ !sne(essar t' ta6e an ele(tr'n a%a &r'm !t. An ele(tr'n l'ses)'tent!al energ %#en !t s#!&ts &r'm a less ele(tr'negat!e at'mt'%ar a m're ele(tr'negat!e 'ne.

• T#e )r'(ess '& (ell"lar res)!rat!'n !s an e/erg'n!( )r'(ess$e(a"se gl"('se !s $e!ng '/!!;e. D"r!ng t#e '/!at!'n )r'(essst're energ &r'm gl"('se !s l!$erate an mae aa!la$le &'rATP snt#es!s. A(t!at!'n energ nees t' $e !neste &'r t#!s)r'(ess. In (ells t#e tem)erat"re !s n't #!g# en'"g# t' )r'!et#e energ s' en;mes %!ll sl'%l $rea6 '%n gl"('se !n a ser!es'& ste)s.

• Ele(tr'ns are sl'%l str!))e &r'm gl"('se an trans&erre t'NAD a ('en;me, t#e er!at!e '& t#e !tam!n n!a(!n.En;mes (alle e#r'genases rem'e * ele(tr'ns an *)r't'ns &r'm t#e s"$strate an (#ange t#e NAD m'le("le !nt'

an NADH. In t#!s )r'(ess t#e s"$strate !s '/!!;e, %#!le t#eNAD !s re"(e.



• Ea(# NADH m'le("le re)resents st're energ t#at (an $eta))e t' ma6e ATP %#en t#e ele(tr'ns ('m)lete t#e!r )at# &r'mt#e NADH t' '/gen.

• D"r!ng (ell"lar res)!rat!'n t#e H rea(ts %!t# '/gen &r'm an'rgan!( m'le("le n't as )"re H* s' t#e rea(t!'n !s less e/)l's!e



!n nat"re. Als' (ell"lar res)!rat!'n "ses an e1e't+*) t+a)s$*+t'#a() t' $rea6 t#e energ release '& ele(tr'ns !nt' seeral ste)s. T#e ele(tr'n trans)'rt (#a!n ('nta!ns a set '& m'le("les m'stl)r'te!ns $"!lt !nt' t#e !nner mem$rane '& t#e m!t'(#'nr!'n.Ele(tr'ns t#at are rem'e &r'm gl"('se 'r 't#er 'rgan!(

m'le("les m'e t' NADH t#an t' t#e ele(tr'n trans)'rt (#a!nt#an t' %ater t' gra"all l'se t#e!r energ.

III. THE STAGES OB CELLULAR RESPIRATION? PRE>IE+• T#ere are t#ree !st!n(t stages '& t#e (ell"lar res)!rat!'n?

o Gl('ls!so T#e (!tr!( a(! ((leo O/!at!e )#'s)#'rlat!'n? ele(tr'n trans)'rt

(#em!'sm's!s

• Onl t#e (!tr!( a(! ((le an '/!at!e )#'s)#'rlat!'n re-"!re'/gen, gl('ls!s 'es n't.

• G1!'*1!s(s – (ata$'l!( )r'(ess t#at $rea6s '%n gl"('se !nt' *)r"ate m'le("les %!t#'"t t#e nee &'r '/gen. T#!s )r'(essta6es )la(e !n t#e (t')lasm. S'me '& t#e ste)s !n gl('ls!s arere'/ )r'(esses t#at )r'"(e NADH m'le("les &r'm NAD. T#eseNADH m'le("les m'e t' t#e )r'(ess '& '/!at!e )#'s)#'rlat!'n



an &"el t#at )r'(ess. A &e% ATP m'le("les are als' )r'"(e !nt#!s )r'(ess.

• C(t+(' a'( '!'1e /K+e5s '!'1e4 7 Ta6es )la(e !n t#e m!t'(#'nr!almatr!/. T#!s )r'(ess ('m)letes t#e $rea6'%n '& a er!at!e '&)r"ates !nt' (ar$'n !'/!e. S'me '& t#e ste)s !n t#e (!tr!( a(!

((le are re'/ )r'(esses t#at )r'"(e NADH m'le("les &r'm NAD

. T#ese NADH m'le("les m'e t' t#e )r'(ess '& '/!at!e)#'s)#'rlat!'n an &"el t#at )r'(ess. A &e% ATP m'le("les areals' )r'"(e !n t#!s )r'(ess.

• O3(at(0e $#*s$#*+!1at(*) – T#e t#!r stage '& (ell"larres)!rat!'n t#at ta6es )la(e 'n t#e !nner mem$rane '& t#em!t'(#'nr!'n. An ele(tr'n trans)'rt (#a!n a((e)ts ele(tr'ns &r'mNADH an BADH* an )asses t#ese ele(tr'ns &r'm 'ne m'le("le t't#e 't#er. T#e energ '& ele(tr'ns !s "se t' &'rm ATP m'le("lesan t#e ele(tr'ns $!n %!t# #r'gen !'ns an '/gen t' &'rm%ater.

• S'me ATP m'le("les are &'rme "r!ng gl('gls!s an t#e (!tr!(a(! ((le $ su5st+ate;1e0e1 $#*s$#*+!1at(*) – a !re(t trans&er'& )#'s)#ate t' ADP m'le("les &r'm an 't#er m'le("le.

• T#e t'tal ATP )r'"(t!'n '& (ell"lar res)!rat!'n !s a$'"t 37 ATPm'le("lesF gl"('se.

I>. GLYCOLYSIS• In t#!s )r'(ess a 4 (ar$'n s"gar !s s)l!t t' )r'"(e * )r"ate

m'le("les.• T#e )r'(ess ('ns!sts '& 19 ste)s %#!(# (an $e !!e !nt' t%'

)#ases?o E)e+! ()0este)t $#ase – "r!ng t#!s )#ase t#e (ell

a(t"all s)ens energ "ses ATP t' )#'s)#'rlate an$rea6 t#e 4 (ar$'n s"gar.

o E)e+! $a!*< $#ase – ATP !s )r'"(e $ s"$strate:leel)#'s)#'rlat!'n an NADH !s als' )r'"(e. T#e netenerg !el &r'm t#!s )r'(ess !s * ATP * NADH &r'meer gl"('se m'le("le.

• T#!s )r'(ess 'es n't re-"!re '/gen. Pr"ates t#at are )r'"(e!n t#!s )r'(ess %!ll $e (#ange t' t t' enter t#e (!tr!( a(! ((le s'

t#e rest '& t#e!r (#em!(al energ (an $e e/tra(te.



>. THE CITRIC ACID CYCLE• I& m'le("lar '/gen !s )resent, t#e t%' )r"ate m'le("les enter

t#e m!t'(#'nr!'n %#ere t#e en;mes '& t#e (!tr!( a(! ((le('m)lete t#e '/!at!'n )r'(ess.

• C'ners!'n '& )r"ate t' a'et!1 C*A !nterme!ate ste)('ns!sts '& t#ree rea(t!'ns t#at are (atal;e $ m"lt!)leen;mes?

o T#e (ar$'/l gr'") !s rem'e &r'm )r"ate an g!en ' as CO* gas

o T#e rema!n!ng * (ar$'n ('m)'"n !s '/!!;e !nt' ana(etate

o A ('en;me A a er!at!e '& !tam!n !s atta(#e t' t#ea(etate, ma6!ng !t er rea(t!e.



• In t#e (!tr!( a(! ((le t#e a(etate !s gra"all $r'6en '%n t' *m're CO* m'le("les, 1 ATP m'le("le, 3 NADH m'le("les anan't#er ele(tr'n (arr!er BADH* )er t"rn * t"rns )er gl"('se.

• T#e NADH an BADH* m'le("les m'e t' t#e ele(tr'n trans)'rt(#a!n %#!le t#e CO* m'le("les are release !nt' t#e $l'' streaman eent"all !nt' t#e a!r "r!ng e/#alat!'n. T#e ATP m'le("les(an $e "se !n en't#erm!( )r'(esses.



>I. OIDATI>E PHOSPHORYLATION• At t#!s )'!nt t#ere !s st!ll a large am'"nt '& energ st're !n t#e 7

NADH an * BADH* m'le("les t#at m'e t' t#e !nner mem$rane'& t#e m!t'(#'nr!'n &r'm gl('ls!s an (!tr!( a(! ((le. T#eele(tr'ns an H !'ns are release an t%' )r'(esses ta6e )la(e?

A. Ele(tr'n Trans)'rt?• Ele(tr'n trans)'rt !s )er&'rme 'n a ('lle(t!'n '& m'le("les t#at

are l'(ate 'n t#e !nner mem$rane '& t#e m!t'(#'nr!'n. T#elarge s"r&a(e t#at !s )r'!e $ t#e (r!stae '& t#e m!t'(#'nr!'nma6es t#'"sans '& t#ese )r'(esses )'ss!$le all at 'n(e. T#ereare &'"r gr'")s '& )r'te!ns !n t#e ele(tr'n trans)'rt (#a!n, t#eare n"m$ere &r'm I t#r'"g# I>. Pr'st#et!( gr'")s are atta(#et' t#em, %#!(# are ne(essar &'r t#e n'rmal &"n(t!'n!ng '& t#e



en;mes. As t#e ele(tr'ns m'e !n t#e ele(tr'n trans)'rt (#a!n,t#e gra"all l'se s'me '& t#e!r &ree energ. T#e ele(tr'n(arr!ers alternate $et%een an '/!!;e an a re"(e stage ast#e r') an ga!n ele(tr'ns.

• Pr'te!ns t#at $"!l t#e ele(tr'n trans)'rt (#a!n are @a')r'te!n,!r'n:s"l&"r )r'te!n, "$!-"!n'ne an seeral '!t*'#+*es ( ('m)le/ )r'te!ns %!t# a #eme gr'") t#at #ae an !r'n !'n t#at(an $e re"(e an '/!!;e.

• e(a"se t#e BADH* m'le("les r') t#e!r ele(tr'ns later !n t#e(#a!n, t#e )r'!e a$'"t 1F3r less energ t#an NADHm'le("les.

• T#e ele(tr'n trans)'rt !s ('")le 'n t#e !nner mem$rane '& t#em!t'(#'nr!'n %!t# an't#er )r'(ess (alle (#em!'sm's!s.

. C#em!'sm's!s• C#e(*s*s(s – energ st're !n t#e &'rm '& #r'gen !'n

gra!ent a(r'ss a mem$rane !s "se t' r!e (ell"lar %'r6 s"(#as t#e snt#es!s '& ATP.



• T#!s )r'(ess als' ta6es )la(e 'n t#e !nner mem$rane '& t#em!t'(#'nr!'n, %#ere man (')!es '& an't#er )r'te!n ('m)le/are l'(ate. T#!s ('m)le/ !s (alle ATP s!)t#ase – an en;met#at ma6es ATP &r'm ADP an !n'rgan!( )#'s)#ate. T#!s en;me%'r6s l!6e an !'n )"m) $"t )"s#es t#e H !'ns !n reerse &r'm

t#e #!g#er t' t#e l'%er ('n(entrat!'n area an "ses t#e)'tent!al energ '& t#e ('n(entrat!'n gra!ent t' &"el ATPsnt#es!s.

• ATP snt#ase !s a ('m)le/ )r'te!n t#at #as seeral s"$"n!ts. Asan H !'n @'%s t#r'"g# a narr'% s)a(e !n t#e en;me, !t r'tatesa )art '& t#e en;me an eer t#ree ele(tr'ns %!ll t#!s %a &'rman ATP m'le("le.

+at(#? #tt)?FF(ell.ns".n'a6.e"Fan!mat!'nsFat)gra!entFm'!e.#tm An #tt)?FF(ell.ns".n'a6.e"Fan!mat!'nsFet(Fm'!e.#tm

http://vcell.ndsu.nodak.edu/animations/atpgradient/movie.htm

http://vcell.ndsu.nodak.edu/animations/etc/movie.htm

http://vcell.ndsu.nodak.edu/animations/atpgradient/movie.htm

http://vcell.ndsu.nodak.edu/animations/etc/movie.htm



• T#e !nner m!t'(#'nr!al mem$rane generates an ma!nta!ns an H gra!ent. T#e gra!ent !s (reate $ t#e ele(tr'n trans)'rt (#a!n $ta6!ng t#e energ '& ele(tr'ns t' )"m) H !'ns a(r'ss t#e !nnermem$rane !nt' t#e !ntermem$rane s)a(e. T#e H !'ns ten t')ass!el )ass $a(6 !nt' t#e m!t'(#'nr!al matr!/ an t#e #ae t'

m'e $a(6 t#r'"g# t#e ATP snt#ase, %#!(# %!ll generate ATPm'le("les. T#e H gra!ent t#at e/!sts a(r'ss t#e !nner mem$rane!s (alle $+*t*);*t(0e 2*+'e.

• C#em!'sm's!s !s an e/am)le '& energ ('")l!ng $e(a"se !t "ses t#eenerg st're !n t#e )r't'n gra!ent a(r'ss a mem$rane t' r!e(ell"lar %'r6.

>II. A BINAL ACCOUNTING?• T#e 'erall &"n(t!'n '& (ell"lar res)!rat!'n !s #arest!ng t#e

energ '& &'' &'r ATP snt#es!s.• Ele(tr'ns @'% !n t#e &'ll'%!ng 'rer? gl"('se → NADH→ ele(tr'n

trans)'rt (#a!n→ )r't'n:m't!e &'r(e → ATP

• T#e nal ATP )r'"(t!'n !s 37 ATP 'r 34 ATP !& t#e less e(!entBAD !s "se &'r m'!ng t#e ele(tr'ns

• T#!s )r'(ess !s a$'"t 09 J e(!ent.



>III. BERENTATION• Bermentat!'n )r'!es a me(#an!sm $ %#!(# s'me (ells (an

'/!!;e 'rgan!( &"el an generate ATP %!t#'"t t#e "se '& '/gen.• Bermentat!'n !s an e/tens!'n '& gl('ls!s t#at (an generate ATP

s'lel $ s"$strate:leel )#'s)#'rlat!'n as l'ng as s"(!ent

s"))l '& NAD !s aa!la$le t' a((e)t ele(tr'ns "r!ng t#e'/!at!'n ste) '& gl('ls!s.

• Bermentat!'n reall ('ns!sts '& gl('ls!s an a!t!'nal rea(t!'nst#at generate NAD $ trans&err!ng ele(tr'ns &r'm NADH t')r"ateKs er!at!es. In t#ese )r'(esses, NAD !s re((le an* ATP m'le("les are )r'"(e &r'm ea(# gl"('se.

• T#ere are seeral !erent t)es '& &ermentat!'n. T#e &'ll'%!ngt%' are t#e m'st ('mm'n?

o A1'*#*1 2e+e)tat(*) – t#e )r"ate !s ('nerte t'et#an'l !n t%' ste)s. Car$'n !'/!e, et#an'l an NAD are t#e )r'"(ts '& t#e )r'(ess. an $a(ter!a an east(arr '"t al('#'l &ermentat!'n. Use $ #"mans !n$re%!ng, %!nema6!ng, $a6!ng.

o La't(' a'( 2e+e)tat(*) – )r"ate !s re"(e t' &'rmla(tate an NAD. N' CO* !s release !n t#!s )r'(ess.O(("rs !n s'me $a(ter!a an &"ng! an %!el "se !n t#ea!r !n"str.



• S'me 'rgan!sms m'stl $a(ter!a (an s"r!e 'n e!t#er&ermentat!'n 'r 'n (ell"lar res)!rat!'n. T#ese 'rgan!sms are(alle 2a'u1tat(0e a)ae+*5s.

• e(a"se gl('ls!s 'es n't re-"!re an '& t#e mem$rane:$'"n'rganelles t' ta6e )la(e, !t !s )er&'rme $ $'t# )r'6ar'tes ane"6ar'tes.

I. CONNECTIONS TO OTHER ETHAOLIC PATH+AYS?• Gl('ls!s an t#e (!tr!( a(! ((le are ma'r !nterse(t!'ns '&

ar!'"s (ata$'l!( an ana$'l!( )at#%as.• 'st '& '"r &'' (al'r!es are '$ta!ne $ eat!ng &ats, )r'te!ns

an ar!'"s (ar$'#rates.



• P'lsa((#ar!es are !geste rst t#at (an '!n t#e )r'(ess '&gl('ls!s !re(tl.

• Pr'te!ns are rst $r'6en '%n !nt' am!n' a(!s %#!(# are m'stl"se t' $"!l ne% )r'te!ns. H'%eer, e/(ess am!n' a(!s %!ll $e('nerte $ en;mes t' !nterme!ates '& gl('ls!s an t#e

(!tr!( a(! ((le. e&'re am!n' a(!s (an enter t#ese )r'(esses,ea()at(*) m"st ta6e )la(e – t#e am!n' gr'")s m"st $erem'e. T#e n!tr'gen ('nta!n!ng %astes are e/(rete !n t#e&'rm '& amm'n!a, "rea 'r "r!( a(!.

• Bats are als' !geste an a$s'r$e. Batt a(!s are $r'6en'%n $ 5eta *3(at(*) !nt' t%' (ar$'n &ragments %#!(# entert#e (!tr!( a(! ((le as a(etl C'A. Bats are e/(ellent &"el. T#erelease t%!(e as man ATP m'le("les as gl"('se 'es )er gram.

• Gl('ls!s an t#e (!tr!( a(! ((le als' &"n(t!'n as meta$'l!(!nter(#anges t#at ena$le '"r (ells t' ('nert s'me 6!ns '&m'le("les t' 't#ers e)en!ng 'n t#e nees '& t#e (ell.

• e(a"se (ell"lar res)!rat!'n !s a meta$'l!( )at#%a t#at !s(atal;e $ a %!e range '& en;mes, en;me reg"lat!'n !s(r"(!al #ere as %ell. Bee$a(6 me(#an!sms an en:)r'"(t!n#!$!t!'n !s ('mm'n !n t#ese )r'(esses. +#en t#ere are a l't '&ATP m'le("les !n t#e (ell, t#e )r'(ess '& gl('ls!s (an $est'))e "nt!l t#ese m'le("les are "se ") !n energ'n!()r'(esses.

CHAPTER => 7 PHOTOSYNTHESIS

OB8ECTIVE 9UESTIONS"T#e P+*'ess T#at Fees t#e B(*s$#e+e1. D!st!ng"!s# $et%een a"t'tr')#!( an #eter'tr')#!( n"tr!t!'n.*. D!st!ng"!s# $et%een )#'t'a"t'tr')#s an (#em'a"t'tr')#s.3. Des(r!$e t#e str"(t"re '& a (#l'r')last, l!st!ng all mem$ranes an('m)artments.

T#e Pat#&a!s *2 P#*t*s!)t#es(s0. +r!te a s"mmar e-"at!'n &'r )#'t'snt#es!s.2. In general terms, e/)la!n t#e r'le '& re'/ rea(t!'ns !n

)#'t'snt#es!s.4. Des(r!$e t#e t%' ma!n stages '& )#'t'snt#es!s !n general terms.5. Des(r!$e t#e relat!'ns#!) $et%een an a(t!'n s)e(tr"m an ana$s'r)t!'n s)e(tr"m. E/)la!n %# t#e a(t!'n s)e(tr"m '&)#'t'snt#es!s !ers &r'm t#e a$s'r)t!'n s)e(tr"m &'r (#l'r')#ll a.7. E/)la!n #'% (ar'ten'!s )r'te(t t#e (ell &r'm amage $ l!g#t.8. L!st t#e %aelengt# '& l!g#t t#at are m'st ee(t!e &'r)#'t'snt#es!s.



19. E/)la!n %#at #a))ens %#en a s'l"t!'n '& (#l'r')#ll a a$s'r$s)#'t'ns. E/)la!n %#at #a))ens %#en (#l'r')#ll a !n t#e (#l'r')lasta$s'r$s )#'t'ns.11. L!st t#e ('m)'nents '& a )#'t'sstem an e/)la!n t#e &"n(t!'n '&ea(# ('m)'nent.

1*. Tra(e t#e m'ement '& ele(tr'ns !n n'n((l!( ele(tr'n @'%. Tra(et#e m'ement '& ele(tr'ns !n ((l!( ele(tr'n @'%.13. E/)la!n t#e &"n(t!'ns '& ((l!( an n'n((l!( ele(tr'n @'%.10. Des(r!$e t#e s!m!lar!t!es an !eren(es !n (#em!'sm's!s $et%een'/!at!e )#'s)#'rlat!'n !n m!t'(#'nr!a an )#'t')#'s)#'rlat!'n !n(#l'r')lasts.12. State t#e &"n(t!'n '& ea(# '& t#e t#ree )#ases '& t#e Cal!n ((le.14. Des(r!$e t#e r'le '& ATP an NADPH !n t#e Cal!n ((le.15. Des(r!$e %#at #a))ens t' r"$!s(' %#en O* ('n(entrat!'n !s m"(##!g#er t#an CO* ('n(entrat!'n.17. Des(r!$e t#e ma'r ('nse-"en(es '& )#'t'res)!rat!'n. E/)la!n %#

!t !s t#'"g#t t' $e an e'l"t!'nar rel!(t.18. Des(r!$e t%' !m)'rtant )#'t'snt#et!( aa)tat!'ns t#at m!n!m!;e)#'t'res)!rat!'n.*9. L!st t#e )'ss!$le &ates '& )#'t'snt#et!( )r'"(ts.

I. O>ER>IE+• L!&e !s )'%ere $ t#e s"n

• L!g#t energ !s ('nerte !nt' (#em!(al energ '& 'rgan!(m'le("les

• Aut*t+*$# – 'rgan!sms t#at ma6e t#e!r 'rgan!( mater!als

%!t#'"t ta6!ng !n 'rgan!( mater!als &r'm an 't#er 'rgan!sm als'(alle )r'"(ers

• Hete+*t+*$#s – '$ta!n t#e!r 'rgan!( mater!als $ eat!ng t#em$e(a"se t#e are "na$le t' ma6e 'rgan!( &r'm !n'rgan!(mater!als (an $e e('m)'sers an ('ns"mers

II. GENERAL RE>IE+ OB THE PHOTOSYNTHETIC PROCESS• All green )arts '& t#e )lant #ae (#l'r')lasts $"t t#e ma!n s!te '&

)#'t'snt#es!s !s t#e leaes.• C#l'r')lasts are !n t#e es*$#!11 se(t!'n '& t#e )lantKs lea&.

CO* enters t#e lea& an O* leaes !t t#r'"g# t#e st*ata – small')en!ngs t#at are ')ene an (l'se $ ua+ 'e11s. G"ar(ells als' reg"late ea)'rat!'n '& %ater.

Figure 10.3 – be able to draw and label the parts of the chloroplast



• C#1*+*$#!11 – green )!gment, !s l'(ate !ns!e '& t#e t#la6'!mem$ranes.

• P#'t'snt#et!( )r'6ar'tes ' n't #ae (#l'r')lasts $"t #ae)#'t'snt#et!( mem$ranes

• A s!m)l!e e-"at!'n '& )#'t'snt#es!s !s?4 CO* 4 H*O l!g#t energ – C4H1*O4 4O*

• T#!s e-"at!'n !s t#e reerse '& t#e 'erall e-"at!'n '& (ell"larres)!rat!'n. T#ese t%' )r'(esses e)en 'n ea(# 't#er &'r t#e!r)r'"(ts.

• Plant (ells are a$le t' )er&'rm $'t# (ell"lar res)!rat!'n an)#'t'snt#es!s, $"t #eter'tr')# 'rgan!sms e)en 'n



a"t'tr')#s t' )r'!e t#e '/gen an 'rgan!( m'le("les t' t#e!r(ell"lar res)!rat!'n.

• P#'t'snt#et!( )r'(esses are als' ma!nl re'/ rea(t!'ns.H'%eer, !n )#'t'snt#es!s t#e ele(tr'n @'% !s reerse. +ater!s s)l!t an ele(tr'ns %!t# #r'gen !'ns are trans&erre &r'm t#e

%ater t' (ar$'n !'/!e t' &'rm s"gar t#r'"g# a ser!es '&re"(t!'n rea(t!'ns. T#e ele(tr'ns !n(rease t#e!r )'tent!alenerg "r!ng t#e )r'(ess. T#!s !n(rease !n )'tent!al energ !s&"ele $ t#e energ '& t#e s"n.

III. THE STAGES OB PHOTOSYNTHESIS

• P#'t'snt#es!s #as t%' ma'r stages %!t# seeral ste)s ea(#. T#ese t%' stages are?

a. 1(#t +ea't(*)s 7 t#ese ste)s ('nert s'lar energt' (#em!(al energ. L!g#t a$s'r)t!'n r!es a

trans&er '& ele(tr'ns an a #r'gen !'n &r'm %atert' an a((e)t'r m'le("le (alle NADP?, %#!(#tem)'rar!l st'res energ!;e ele(tr'ns. +ater !ss)l!t t' re&"el t#e (#l'r')#ll %!t# ele(tr'ns an)r'"(e O* as a $)r'"(t. T#e l!g#t rea(t!'ns als'generate ATP $ "s!ng (#em!'sm's!s t' )'%er t#ea!t!'n '& a )#'s)#ate gr'") t' ADP –$#*t*$#*s$#*+!1at(*). T#e l!g#t rea(t!'n ta6es)la(e !n t#e t#la6'!s '& t#e (#l'r')last.



$. Ca10() '!'1e 7 T#!s ((le $eg!ns $ !n('r)'rat!ngCO* &r'm t#e a!r !nt' 'rgan!( m'le("les alrea)resent !n t#e (#l'r')last – 'a+5*) @3at(*). T#e((le re"(es t#e /e (ar$'n !nt' a (ar$'#rate$ a!ng ele(tr'ns &r'm t#e NADPH m'le("les '&

t#e l!g#t rea(t!'ns. T#!s )r'(ess re-"!res energt#at ('mes &r'm t#e ATP m'le("les &r'm t#e l!g#trea(t!'ns. Alt#'"g# t#!s )r'(ess 'es n't re-"!rel!g#t !t st!ll "s"all '(("rs "r!ng t#e al!g#t$e(a"se NADPH an ATP are m'stl aa!la$le att#at t!me. T#e Cal!n ((le ta6es )la(e !n t#estr'ma '& t#e (#l'r')last.



I>. THE PROCESSES OB THE LIGHT REACTIONA. LIGHT AND LIGHT ASORPTION

• L!g#t !s a &'rm 'n ele(tr'magnet!( energ ele(tr'magnet!(

ra!at!'n. T#e !stan(e $et%een t#e (rests '& ele(tr'magnet!(%aes !s (alle t#e &a0e1e)t#. T#e ent!re range '& ra!at!'n !s6n'%n as t#e e1e't+*a)et(' s$e't+u. T#e m'st !m)'rtantsegment '& t#!s s)e(tr"m !s t#e 379 nm – 529 nm range '&%aelengt#. T#!s range !s 6n'%n as 0(s(51e 1(#t. T#!s !s als't#e range '& energ t#at r!es )#'t'snt#es!s.

• +#en l!g#t meets matter, s'me '& t#e l!g#t %!ll $e a$s'r$e,re@e(te $a(6 'r transm!tte. S"$stan(es t#at a$s'r$ !s!$le

l!g#t are 6n'%n as )!gments. D!erent )!gments a$s'r$ !erent%aelengt# '& l!g#t an t#at l!g#t !sa))ears. T#e ('l'rs %#at%e see are t#e ('l'rs t#at are re@e(te $a(6 &r'm a s"$stan(e.C#1*+*$#!11 a$s'r$s !'let:$l"e an re l!g#t %#!le transm!tt!ngan re@e(t!ng green l!g#t.



• T#e a$!l!t '& a )!gment t' a$s'r$ ar!'"s %aelengt# '& l!g#t(an $e meas"re $ "s!ng s$e't*$#*t*ete+s.



• A gra)# )l'tt!ng a )!gmentKs l!g#t a$s'r)t!'n ers"s %aelengt#!s (alle a5s*+$t(*) s$e't+u.

• T#e a$s'r)t!'n s)e(tr"m '& (#l'r')lasts reeals t#e )resen(e '&t#ree !erent )!gments t#at r!e )#'t'snt#es!s? (#l'r')#ll a,(#l'r')#ll $ an (ar'ten'!s. C#l'r')#ll a !s t#e ma!na$s'r)t!'n )!gment $"t (#l'r')#ll $ an (ar'ten'!s als' #el)t' ma6e l!g#t a$s'r)t!'n m're e(!ent a((ess'r )!gments.Car'ten'!s als' )r'!e )#'t')r'te(t!'n aga!nst e/(ess!e l!g#t

t#at %'"l 't#er%!se amage (#l'r')#ll.



. E/(!tat!'n '& C#l'r')#ll $ L!g#t• +#en a m'le("le a$s'r$s (erta!n %aelengt# '& l!g#t, t#e

m'le("leKs ele(tr'ns a$s'r$ t#e energ an m'e t' a #!g#erenerg leel %!ll #ae #!g#er )'tent!al energ. T#e )#'t'nst#at are a$s'r$e #ae t#e e/a(t same energ as t#e energ

!eren(e $et%een t#e gr'"n state an e/(!te state '& t#eele(tr'n. T#!s !s %# ea(# )!gment #as a "n!-"e a$s'r)t!'ns)e(tr"m.

• T#e e/(!te state '& t#e ele(tr'n !s "nsta$le s' ele(tr'ns releaset#!s e/(ess energ er -"!(6l. T#!s !s t#e reas'n %# a(#l'r')#ll e/tra(t gl'%s !n t#e ar6 an releases #eat.



C. P#'t'sstems?• In t#e t#la6'! '& t#e (#l'r')last, (#l'r')#ll m'le("les are

'rgan!;e %!t# 't#er a((ess'r )!gments an )r'te!ns !nt')#'t'sstems.

• P#*t*s!stes are ('m)'se '& a rea(t!'n (enter t#at !ss"rr'"ne $ a n"m$er '& l!g#t:#arest!ng ('m)le/es. Ea(#l!g#t:#arest!ng ('m)le/ !s ('m)'se '& )!gment m'le("les t#atare $'"n t' )art!("lar )r'te!ns. T#e a!t!'nal )!gmentm'le("les ma6e !t )'ss!$le t' #arest energ 'er a largers"r&a(e an a larger )'rt!'n '& t#e s)e(tr"m t#an a s!ngle)!gment %'"l '.

• B!rst a )!gment m'le("le a$s'r$s energ an !ts ele(tr'ns m'et' t#e e/(!te state, t#en ele(tr'ns ret"rn t' t#e!r gr'"n statean )ass t#e energ 'n t' an 't#er )!gment m'le("le. T#eenerg eent"all ens ") !n t#e rea(t!'n (enter. T#e +ea't(*)

'e)te+ !s a )r'te!n ('m)le/ t#at !n(l"es t%' s)e(!al (#l'r')#lla m'le("les an a m'le("le (alle t#e $+(a+! e1e't+*)a''e$t*+.

• T#e rst ste) '& t#e l!g#t rea(t!'n !s %#en t#e (#l'r')#ll am'le("le releases an ele(tr'n t#at !s ta6en $ t#e )r!marele(tr'n a((e)t'r. T#e ele(tr'n a((e)t'r !s re"(e an t#e(#l'r')#ll a m'le("le !s '/!!;e.



• T#e t#la6'! mem$rane #as t%' t)es '& )#'t'sstems t#at %'r6

t'get#er !n t#e l!g#t rea(t!'n '& )#'t'snt#es!s. T#ese)#'t'sstems are $#*t*s!ste II /PS II4 an $#*t*s!ste I /PSI4. Ea(# )#'t'sstem #as a (#ara(ter!st!( rea(t!'n (enter %!t# a)art!("lar t)e '& )r!mar ele(tr'n a((e)t'r an t#e (#l'r')#ll am'le("les are ass'(!ate %!t# a (#ara(ter!st!( )r'te!n.

• T#e rea(t!'n (enter (#l'r')#ll a '& PSII !s 6n'%n as P479 $e(a"set#!s )!gment !s $est at a$s'r$!ng l!g#t at t#e %aelengt# '& 479 nm. T#e rea(t!'n (enter (#l'r')#ll a '& PSI !s 6n'%n as P599 $e(a"set#!s )!gment !s $est at a$s'r$!ng l!g#t at t#e %aelengt# '& 599 nm. T#ese (#l'r')#ll m'le("les #ae !erent a$s'r)t!'n %aelengt#s$e(a"se '& t#e ass'(!ate )r'te!ns t#at t#e $!n %!t#.

III. THE LIGHT REACTIONS

A. N'n((l!( Ele(tr'n Bl'% – L!g#t Rea(t!'ns



• L!g#t r!es t#e snt#es!s '& NADPH an ATP m'le("les $

energ!;!ng t#e t%' )#'t'sstems !n t#e t#la6'! mem$ranes '&(#l'r')lasts.

• T#e ste)s '& t#!s )r'(ess are t#e &'ll'%!ng?1. A )#'t'n '& l!g#t str!6es a )!gment m'le("le !n a l!g#t #arest!ng

('m)le/. T#!s energ !s gra"all )asse 'n t' t#e (#l'r')#ll am'le("le !n t#e PS II. It e/(!tes 'ne '& t#e ele(tr'ns t' a #!g#erenerg state.

*. T#e ele(tr'n !s (a)t"re $ t#e )r!mar ele(tr'n a((e)t'r.3. An en;me s)l!ts a %ater m'le("le t' re)la(e t#e ele(tr'n '& t#e

)#'t'sstem t#at %as l'st t' t#e )r!mar ele(tr'n a((e)t'r. Int#!s )r'(ess O* !s &'rme t#at !s release &r'm t#e (#l'r')last.

0. T#e ele(tr'n &r'm t#e )r!mar ele(tr'n a((e)t'r !s )asset#r'"g# an ele(tr'n trans)'rt (#a!n t#at !s mae ") '& a)last'-"!n'ne, a (t'(#r'me an )last'(an!n.

2. As t#e ele(tr'ns are m'e t#r'"g# t#e ele(tr'n trans)'rt (#a!n,t#e gra"all l'se t#e!r energ t#at !s "se t' &"el t#e snt#es!s'& ATP.

4. ean%#!le, l!g#t energ als' e/(!tes an ele(tr'n !n t#e PSIrea(t!'n (enter. T#!s ele(tr'n !s als' m'e 'n t' a )r!mar



ele(tr'n a((e)t'r. T#e m!ss!ng ele(tr'n &r'm (#l'r')#ll a !sre)la(e $ t#e ele(tr'n '& PSII t#at %as )asse 'n t#r'"g# t#eele(tr'n trans)'rt (#a!n.

5. T#e ele(tr'n &r'm t#e se('n )r!mar ele(tr'n a((e)t'r !s)asse 'n t' a )r'te!n (alle &erre'/!n.

7. T#e en;me NADP

re"(tase trans&ers ele(tr'ns &r'm &erre'/!nt' NADP t' &'rm NADPH.

. C(l!( Ele(tr'n Bl'%

• Uner (erta!n ('n!t!'ns 'nl )#'t'sstem I !s "se !n t#e l!g#trea(t!'n $"t n't )#'t'sstem II. In t#!s (ase t#e ele(tr'ns ((le$a(6 &r'm &erre'/!n t' t#e (t'(#r'me ('m)le/ an &r'm t#at t't#e P599 (#l'r')#ll a.

• T#!s )r'(ess 'es n't )r'"(e NADPH an 'es n't release '/genan "se 'nl t' generate ATP.

• T#!s ((l!( )r'(ess !s "se&"l, !& t#ere !s )lent '& NADPH aa!la$le$"t t#ere !s a nee &'r ATP !n t#e Cal!n ((le. T#e Cal!n ((le !ngeneral nees m're ATP t#an NADPH s' t#e !eren(e !s mae ")$ "s!ng t#e ((l!( ele(tr'n @'%.

• NADPH seems t' $e t#e reg"lat'r t#at eterm!nes %#!(# )r'(essta6es )la(e – +eu1at(*) () t#e 'e11

D. C'm)ar!ng C#em!'sm's!s !n C#l'r')lasts an !n !t'(#'nr!a



• T#e ele(tr'n trans)'rt (#a!n !s l'(ate 'n a mem$rane !n $'t#an !t !s (l'se t' ATP snt#ase !n $'t#. S'me '& t#e ele(tr'n(arr!er )r'te!ns are als' s!m!lar, s' as t#e str"(t"re '& ATPsnt#ase.

• H'%eer, t#ere are man !eren(es as %ell. H!g#:energele(tr'ns are ta6en &r'm 'rgan!( m'le("les !n m!t'(#'nr!a. In(#l'r')last, t#ese ele(tr'ns are energ!;e $ (a)t"r!ng l!g#tenerg.

• T#e !nner mem$rane '& m!t'(#'nr!a )"m)s )r't'ns &r'm t#em!t'(#'nr!al matr!/ '"t t' t#e !ntermem$rane s)a(e %#!(# t#an

seres as a reser'!r '& #r'gen !'n. T#!s ('n(entrat!'n an)'tent!al !eren(e $et%een t#e t%' s!es '& t#e !nnermem$rane &"els t#e snt#es!s '& ATP m'le("les.

• T#e t#la6'! mem$rane '& t#e (#l'r')last )"m)s #r'gen !'ns&r'm t#e str'ma !nt' t#e t#la6'! s)a(e. ATP !s &'rme %#en#r'gen !'ns m'e '%n t#e ('n(entrat!'n gra!ent $a(6 t' t#estr'ma t#r'"g# ATP snt#ase. +#en !ll"m!nate, t#e t#la6'!s)a(e #as a )H '& 2 %#!le t#e str'ma #as a )H '& 7, s' t#ere !s a



s"$stant!al )H an H ('n(entrat!'n !eren(e $et%een t#e t%'s!es '& t#e t#la6'! mem$rane.

Figure 10.17 – summary of the light reactions

Watch:http://cell.ndsu.noda!.edu/animations/photosynthesis/moie.htm andhttp://cell.ndsu.noda!.edu/animations/photosystem""/moie.htm I>. THE CAL>IN CYCLE USES ATP AND NADPH TO CON>ERT CO* TOSUGAR• T#e Cal!n ((le !s an ana$'l!( ((le t#at $"!ls s"gar &r'm smaller

m'le("les %#!le "s!ng energ. Car$'n enters t#e ((le !n t#e &'rm'& CO*. T#e ((le als' re-"!res ATP )r'!es energ an NADPH)r'!es re"(!ng )'%er !n t#e &'rm '& #!g# energ ele(tr'ns, als')r'!es H !'ns. T#e (ar$'#rate t#at !s !re(tl )r'"(e !n t#e

((le !s a 3 (ar$'n m'le("le (alle 1!'e+a1e#!es;;$#*s$#ate /GP4. B'r t#e snt#es!s '& 1 gl"('se m'le("le t#e((le nees t' t"rn 3 t!mes. T' s!m)l!& t#!s &a(t %e &'ll'% 3m'le("les '& CO* at t#e same t!me?

o P#ase =" Ca+5*) @3at(*) – T#e ((le !n('r)'rates 3 CO* m'le("les 'ne at a t!me $ atta(#!ng !t t' a e:(ar$'ns"gar name r!$"l'se $!s)#'s)#ate R"P. T#e en;me t#at(atal;es t#!s rst ste) !s R"P (ar$'/lase 'r +u5(s'* er

http://vcell.ndsu.nodak.edu/animations/photosynthesis/movie.htm

http://vcell.ndsu.nodak.edu/animations/photosystemII/movie.htm

http://vcell.ndsu.nodak.edu/animations/photosynthesis/movie.htm

http://vcell.ndsu.nodak.edu/animations/photosystemII/movie.htm



l!6el t#e m'st a$"nant )r'te!n 'n Eart#. T#e )r'"(t '&t#e rst )#ase !s 4 m'le("les '& 3:)#'s)#'gl(erate * &'rea(# CO*.

o P#ase ? Reu't(*) – ATP )#')#'rlates t#e 3:)#'s)#'gl(erate m'le("les 1 ATP &'r ea(# m'le("le – 4 ATP

)er gl"('se t' energ!;e t#ese m'le("les. S"$se-"entrea(t!'ns als' "se 1 NADPH )er m'le("le 4 )er gl"('se t')r'"(e 4 G3P m'le("les. O"t '& t#e 4 )r'"(e G3Pm'le("les, 'nl 1 %!ll leae t#e ((le t' &'rm gl"('se. T#erest '& t#e G3P m'le("les m'e 'n t' t#e ne/t )#ase.

o P#ase ? Ree)e+at(*) *2 RuBP 7 In a ('m)le/ ser!es '&rea(t!'ns G3P !s rearrange t' &'rm R"P. T#!s rea(t!'nre-"!res 3 m're m'le("les '& ATP.

• B'r t#e net snt#es!s '& 'ne G3P m'le("le, t#e Cal!n ((le('ns"mes a t'tal '& n!ne m'le("les '& ATP an 4 m'le("les '&

NADPH. T#ese ('me &r'm t#e l!g#t rea(t!'n. G3P !s t#an "se t'snt#es!;e all 't#er 'rgan!( m'le("les t#at !s "se $ l!!ng'rgan!sms.

>. ALTERNATI>E ECHANISS OB CARON BIATION ADAPTATIONS TOHOT, DRY CLIATESA. P#'t'res)!rat!'n an C3 )lants



• Plants #ae t' ('m)r'm!se $et%een l's!ng t'' m"(# %ater anta6!ng !n en'"g# CO* $e(a"se $'t# trans)!rat!'n an gas e/(#ange&'r )#'t'snt#es!s ta6es )la(e t#r'"g# t#e st'mata '& t#e lea&.

• P#*t*+es$(+at(*)? +#en t#ere !s a s#'rtage '& CO* $e(a"se t#est'mata '& )lants are )art!all (l'se 'n #'t, r as, t#e Cal!n

((le !s stare an t#e )lant )r'"(es less s"gar. +#en r"$!s(''es n't #ae aa!la$le CO* !t as O* t' t#e Cal!n ((le. O/genae t' t#e Cal!n ((le res"lts !n t#e release '& t%' (ar$'n'rgan!( m'le("les. T#ese 'rgan!( m'le("les are )!(6e ") $m!t'(#'nr!a an )er'/!s'mes an $r'6en '%n !nt' CO*.H'%eer, t#!s )r'(ess 'es n't generate ATP !n &a(t !t ('ns"mesATP an !s %aste&"l &'r )lants. P#'t'res)!rat!'n als' re"(es (r')!els an %!t# t#at &'' s"))l!es.

• P#'t'res)!rat!'n !s ('mm'n !n )lants (alle C;$1a)ts. E/am)les '& t#ese are r!(e, %#eat, s' $eans.

. C0 Plants• C P1a)ts are name $e(a"se t#e #ae an alternat!e m'e '&

(ar$'n /at!'n $e&'re t#e Cal!n ((le ta6es )la(e. T#e &'rm a&'"r (ar$'n ('m)'"n t#at st'res CO* "nt!l !t enters t#e Cal!n((le.

• T#ese )lants #ae a "n!-"e anat'm t#at all'%s t#e alternat!e)r'(ess t' ta6e )la(e. T#e #ae t%' !erent )#'t'snt#et!( (ells– es*$#!11 'e11s an 5u)1e;s#eat# 'e11s. "nle s#eat# (ellsare l'(6e a%a &r'm #!g# leels '& '/gen an t#e are arrange!n a t!g#t (!r(le ar'"n t#e e!ns '& t#e lea&. es')#ll (ells arel''sel arrange ar'"n t#e $"nle:s#eat# (ells. T#e Cal!n ((leta6es )la(e !n t#e $"nle:s#eat# (ells %#!le t#e !n('r)'rat!'n '& CO*

ta6es )la(e !n t#e mes')#ll (ells.• T#e ste)s '& t#e C0 )at#%a are t#e &'ll'%!ng?

o In t#e mes')#ll (ells t#e en;me PEP 'a+5*3!1ase ta6es !nCO* an as !t t' a m'le("le '& PEP )#'s)#'en'l)r"ate.

o T#e )r'"(e &'"r:(ar$'n m'le("le m'es t#e CO* !nt' t#e$"nle:s#eat# (ells !a )lasm'esmata.

o In t#e $"nle:s#eat# (ells CO* !s release an enters t#eCal!n ((le.

• +!t# t#e C0 )r'(ess )#'t'res)!rat!'n !s m!n!m!;e an t#e

)r'"(t!!t '& t#e )lant !s !n(rease. T#!s )r'(ess !s es)e(!all$ene(!al 'n r, #'t (l!mates, %#ere t#e st'mata are )art!all(l'se "r!ng t#e a t' )reent e/(ess!e trans)!rat!'n.

• E/am)les '& C0 )lants are ('rn, s"gar(ane.



C. CA Plants• CA aa)tat!'n e'le !n s"(("lent )lants (a(t!, )!nea))les.

T#ese )lants ')en t#e!r st'mata at n!g#t t' ta6e !n CO* an (l'set#em "r!ng t#e a t' )reent trans)!rat!'n.

• T#e )lants ta6e !n CO* at n!g#t an !n('r)'rate !t !nt' a ar!et '&'rgan!( a(!s t#e CA a$$re!at!'n ('mes &r'm (rass"la(ean a(!meta$'l!sm. T#e mes')#ll (ells st're t#e 'rgan!( a(!s !n t#e!ra("'les an "r!ng t#e a %#en ATP an NADPH are )r'"(e !n

t#e l!g#t e)enent )r'(ess, t#e (an "se CO* &'r ma6!ng s"gars !nt#e Cal!n ((le. In CA ((le t#e (ar$'n /at!'n '(("rs at!erent t!mes $"t !n t#e same (ells lea& mes')#ll.





CHAPTER 11 – CELL COUNICATION

OB8ECTIVE 9UESTIONS"1. Des(r!$e t#e $as!( s!gnal:trans"(t!'n )at#%a "se &'r mat!ng !neast. E/)la!n %# %e $el!ee t#ese )at#%as e'le $e&'re t#e rst

m"lt!(ell"lar 'rgan!sms a))eare 'n Eart#.*. Dene <)ara(r!ne s!gnal!ng= an g!e an e/am)le.3. Dene l'(al reg"lat!'n an e/)la!n %# #'rm'nes are n't l'(alreg"lat'rs.0. E/)la!n #'% )lant an an!mal #'rm'nes trael t' target (ells.2. L!st an $r!e@ ene t#e t#ree stages '& (ell s!gnal!ng.

S()a1 Re'e$t(*) a) t#e I)(t(at(*) *2 T+a)su't(*)4. Des(r!$e t#e nat"re '& a l!gan:re(e)t'r !ntera(t!'n an state #'%m"(# !ntera(t!'ns !n!t!ate a s!gnal:trans"(t!'n sstem.5. State %#ere s!gnal re(e)t'rs ma $e l'(ate !n target (ells.

7. C'm)are an ('ntrast G:)r'te!n:l!n6e re(e)t'rs, tr's!ne:6!nasere(e)t'rs, an l!gan:gate !'n (#annels.

S()a1;T+a)su't(*) Pat#&a!s8. Des(r!$e t%' aantages '& "s!ng a m"lt!ste) )at#%a !n t#e

trans"(t!'n stage '& (ell s!gnal!ng.19. E/)la!n #'% t#e 'r!g!nal s!gnal m'le("le (an )r'"(e a

(ell"lar res)'nse %#en !t ma n't een enter t#e target (ell.11. Des(r!$e #'% )#'s)#'rlat!'n )r')agates s!gnal

!n&'rmat!'n.1*. E/)la!n %# a s!ngle (ell ma re-"!re #"nres '& !erent

)r'te!n 6!nases.13. E/)la!n #'% )r'te!n )#'s)#atases t"rn ' s!gnal:

trans"(t!'n )at#%as.10. Dene t#e term <se('n messenger=. r!e@ es(r!$e t#e

r'le '& t#ese m'le("les !n s!gnal!ng )at#%as.12. Des(r!$e #'% ((l!( AP !s &'rme an #'% !t )r')agates

s!gnal !n&'rmat!'n !n target (ells.14. Des(r!$e #'% t#e (t's'l!( ('n(entrat!'n '& Ca* (an $e

altere an #'% t#e !n(rease )''l '& Ca* !s !n'le %!t#trans"(t!'n.

Ce11u1a+ Res$*)ses t* S()a1s15. Des(r!$e #'% s!gnal !n&'rmat!'n !s trans"(e !nt' (ell"lar

res)'nses !n t#e (t')lasm an !n t#e n"(le"s.17. Des(r!$e #'% s!gnal am)l!(at!'n !s a(('m)l!s#e !n target

(ells.18. E/)la!n %# !erent t)es '& (ells ma res)'n !erentl

t' t#e same s!gnal m'le("le.



*9. E/)la!n #'% s(a'l!ng )r'te!ns #el) t' (''r!nate a (ellKsres)'nse t' !n('m!ng s!gnals.

I. O>ER>IE+?

• Cell:t':(ell ('mm"n!(at!'n ma6es !t )'ss!$le t' (''r!natea(t!!t!es am'ng (ells !n m"lt!(ell"lar 'rgan!sms, $"t !t !s als'!m)'rtant !n "n!(ell"lar 'rgan!sms.

• In t#!s (#a)ter %e %!ll &'("s 'n t#e ma!n me(#an!sms $ %#!(#(ells re(e!e, )r'(ess an res)'n t' (#em!(al s!gnals sent &r'm't#er (ells.

II. E/ternal S!gnals – Internal Res)'nsesA. E'l"t!'n '& Cell S!gnal!ng• One t)e '& (ell s!gnal!ng !n #accharomyces c. !s "se t' !ent!&

t#e!r mates. One mat!ng t)e a releases a (#em!(al a t#at

$!ns t' t#e )r')er re(e)t'r '& mat!ng t)e α, %#!le !t releases a&a(t'r α t#at $!ns t' a re(e)t'r '& t#e a (ell. T#ese t%' (ells %!llstart t' gr'% (l'ser t' ea(# 't#er "nt!l t#e ('m)letel "n!te. T#!s &"s!'n %!ll res"lt !n a ne% set '& genet!( ('m$!nat!'ns &r'm$'t# 'rgan!sms.



• C#anges !ns!e '& (ells (an $e $r'"g#t 'n $ a s()a1t+a)su't(*) $at#&a! 7 t#e )r'(ess $ %#!(# a (#em!(als!gnal 'n t#e s"r&a(e '& a (ell !s ('nerte !nt' a s)e(!( (ell"larres)'nse !ns!e t#e (ell.

• 'le("lar )at#%as '& (ell s!gnal!ng are er s!m!lar !n s!m)le'rgan!sms s"(# as east an !n m're ('m)le/ 'rgan!sms s"(# as#"mans. T#!s )r'es t#at t#ese s!gnal!ng me(#an!sms are eran(!ent an eel')e earl !n e'l"t!'n.

. L'(al an L'ng:D!stan(e S!gnal!ng• S'me s!gnals !re(tl ee(t ne!g#$'r!ng (ells (ell "n(t!'ns an(ell:(ell re('gn!t!'n – !re(t ('mm"n!(at!'n



• L*'a1 +eu1at*+s 7 messenger m'le("les t#at are se(rete $s!gnal (ells an trael 'nl t' s#'rt !stan(es.

o N"mer'"s s"rr'"n!ng (ells (an re(e!e t#ese s!gnalsan res)'n t' !t. E/. Gr'%t# &a(t'rs – ma6e (ells !n

t#e !(!n!t gr'% an m"lt!)l In an!mals t#!s l'(als!gnal!ng !s (alle $a+a'+()e s()a1().

o S!)a$t(' s()a1() 7 !s als' a l'(al s!gnal t)e $"t!t '(("rs !n t#e an!mal ner'"s sstem. An ele(tr!(als!gnal traels al'ng t#e nere (ell an tr!ggers t#erelease '& s)e(!( (#em!(als (alle)eu+*t+a)s(tte+s. T#!s s!gnal traels a(r'ss aga) sna)se $et%een t#e ne!g#$'r!ng (ells anst!m"lates t#e target (ell.

• L'(al s!gnal!ng !s n't "nerst'' !n )lants.

• L'ng:!stan(e s!gnal!ng ae(ts s)e(!( target (ells t#at are &ara%a !n t#e $' &r'm t#e reg"lat'r (ells. E/am)les?

o E)*'+()e 'e11s 7 #*+*)e releas!ng (ells t#atrelease #'rm'nes !nt' t#e essels '& t#e (!r("lat'rsstem $ %#!(# t#e trael t' t#e target (ells. Plant#'rm'nes &re-"entl rea(# t#e!r target (ells $m'!ng &r'm (ell t' (ell 'r t#r'"g# t#e a!r 'r s'!l.



o Transm!ss!'n '& nere s!gnals (an als' $e ('ns!erel'ng:!stan(e s!gnals %#en t#e l'ng nere (ells (arrt#e !m)"lse t' ar!'"s )arts '& t#e $' an ('nertst#e ele(tr!( s!gnal $a(6 t' a (#em!(al s!gnal t#at(r'sses a sna)se

• N' matter %#at t)e '& s!gnal !s re(e!e, t#e target (ell m"st#ae a s)e(!( re(e)t'r m'le("le t' re(e!e t#e s!gnal, t#!ss!gnal als' m"st $e t+a)su'e :: (#ange !nt' an 't#er &'rmt#at !s "sea$le &'r t#e (ell.

C. T#e T#ree Stages '& Cell S!gnal!ng• Re'e$t(*) – T#e target (ell ete(ts a s!gnal m'le("le ('m!ng

&r'm '"ts!e '& t#e (ell. T#e s!gnal m'le("le m"st $!n t' are(e)t'r m'le("le 'n t#e (ellKs s"r&a(e t' $e ete(te.

• T+a)su't(*) – T#e $!n!ng '& t#e s!gnal m'le("le (#anges t#ere(e)t'r )r'te!n an !n!t!ates t#e )r'(ess '& trans"(t!'n –('nert!ng t#e s!gnal t' a "se&"l &'rm t#at %!ll generate (#anges!n t#e (ell. Trans"(t!'n s'met!mes '(("rs !n a s!ngle ste) $"t !nm'st (ases !t re-"!res a seeral (#anges !n man m'le("les !nt#e (ell – t#!s !s (alle a s()a1 t+a)su't(*) $at#&a!

• Res$*)se 7 t#e trans"(e s!gnal tr!ggers s'me 6!n '& (#ange!ns!e '& t#e (ell en;me a(t!at!'n, rearrangement '& t#e(t's6elet'n, a(t!at!'n '& genes et(.



http://learn.genetics.utah.edu/content/begin/cells/cellcom/

III. SIGNAL RECEPTION• A re(e)t'r )r'te!n 'n 'r !n t#e target (ell %!ll $e a$le t' ete(t

t#e s!gnal m'le("le $ a mat(#!ng ('m)lementar s#a)es. T#es!gnal m'le("le a(ts as a 1(a) $ s)e(!(all $!n!ng t' as)e(!( m'le("le, '&ten a larger 'ne.

• L!gan $!n!ng "s"all (a"ses a re(e)t'r t' "nerg'('n&'rmat!'n s#a)e (#ange. T#!s (#ange "s"all !re(tla(t!ates t#e re(e)t'r t' !ntera(t %!t# 't#er m'le("les !ns!e t#e

(ell. In s'me !nstan(es re(e)t'r $!n!ng (a"ses t#e aggregat!'n'& t%' 'r m're re(e)t'rs an (a"ses &"rt#er (ell"lar (#anges.

• 'st re(e)t'rs are )r'te!n m'le("les. T#e!r l!gans are large%ater:s'l"$le m'le("les t#at (ann't )ass t#r'"g# t#e (ellmem$rane eas!l. H'%eer, s'me '& t#e re(e)t'rs are l'(ate!ns!e t#e (ell.

A. Intra(ell"lar Re(e)t'rs?• Intra(ell"lar re(e)t'r )r'te!ns are &'"n !ns!e t#e (t')lasm 'r

!n t#e n"(le"s '& t#e target (ells. T#e l!gans !n t#ese (ases

m"st $e a$le t' )ass t#r'"g# t#e (ell mem$rane t' rea(# t#ere(e)t'r. S!gnal m'le("les (an ' t#!s $ $e!ng #r')#'$!( 'rsmall t' (r'ss t#e )#'s)#'l!)!s $!laer. E/am)les '& l!ganst#at (an )ass t#r'"g# t#e (ell mem$rane !n(l"es ster'!s,t#r'!, n!tr!( '/!e NO.





• T#e #'rm'ne:re(e)t'r ('m)le/ !s a$le t' reg"late genee/)ress!'n $ a(t!ng as a t+a)s'+($t(*) 2a't*+ t#at t"rns 'ns)e(!( genes. In (ases '& re(e)t'rs t#at get !nt' t#e n"(le"s,t#e re(e)t'r an l!gan ('m)le/ (an (arr '"t t#e ent!re

re(e)t!'n an trans"(t!'n )r'(ess• an '& t#e !ntra(ell"lar re(e)t'r )r'te!ns #ae s!m!lar str"(t"res

t#at s"ggest t#e!r ('mm'n e'l"t!'nar 'r!g!n.

. Re(e)t'rs !n T#e Plasma em$rane?



• +ater:s'l"$le s!gnal m'le("les $!n t' re(e)t'r m'le("les 'n t#es"r&a(e '& t#e )lasma mem$rane. T#ese re(e)t'rs #ae t'(#ange s#a)e 'r aggregate t' )er&'rm trans"(t!'n.

• T#ree ma'r t)es '& mem$rane re(e)t'rs an t#e!r &"n(t!'n?

• G;$+*te();1()e +e'e$t*+" t#ese re(e)t'rs are l'(ate

!n t#e (t')lasm !ntegral )r'te!ns an %'r6 %!t# a G;$+*te() a gr'") '& )r'te!ns t#at are !n'le !n se('nmessenger (as(ae me(#an!sms. an !erent s!gnalm'le("les (an "se G:)r'te!n l!n6e re(e)t'rsne"r'transm!tters, #'rm'nes s"(# as e)!ne)#r!ne 'r eastmat!ng &a(t'rs. an $a(ter!a (a"se !seases $)r'"(!ng t'/!ns t#at !nterene %!t# G:)r'te!n &"n(t!'n. T#ese re(e)t'rs %'r6 t#e &'ll'%!ng %a?

1. T#e G:)r'te!n a(ts as a m'le("lar s%!t(# %#!(# !s e!t#er 'n'r ', e)en!ng 'n %#!(# '& t#e t'% g"an!ne n"(le't!es!s atta(#e, GDP 'r GTP. +#en GDP !s atta(#e t' t#e

)r'te!n, t#e )r'te!n !s !na(t!e.

*. +#en a mat(#!ng s!gnal m'le("le $!ns t' t#e re(e)t'rm'le("le, t#e re(e)t'r !s a(t!ate an (#anges s#a)e. T#e (#ange !n s#a)e a(t!ates t#e G:)r'te!n, s' !t re)la(es!ts GDP %!t# a GTP.



3. T#e a(t!ate G:)r'te!n !ss'(!ates &r'm t#e re(e)t'r,m'es t' an en;me an alters !t. +#en t#e en;me !sa(t!ate, !t tr!ggers a (ell"lar res)'nse.

0. T#e G )r'te!n (#anges $a(6 t' !ts !na(t!e &'rm an ret"rns

t' t#e re(e)t'r m'le("le.

• Re'e$t*+ T!+*s()e K()ase 7 (an tr!gger m're t#an 'nes!gnal trans"(t!'n )at#%a at 'n(e, #el)!ng t#e (ell reg"latean (''r!nate man as)e(ts '& (ell gr'%t# an (ellre)r'"(t!'n. M!nase !s an en;me t#at (atal;es t#e trans&er'& )#'s)#ate gr'")s. +#en t#e 6!nase )r'te!n !s a(t!ate $t#e s!gnal m'le("le t#r'"g# t#e re(e)t'r, t#e )r'te!n )!(6s ")man )#'s)#ate gr'")s &r'm ATP m'le("les. T#e a(t!ate('m)le/ !s a$le t' a(t!ate seeral 19 'r m're )at#%as 'r

(ell"lar res)'nses !n t#e (ell at 'n(e. A$n'rmal re(e)t'rtr's!ne 6!nases t#at &"n(t!'n !n t#e a$sen(e '& s!gnalm'le("les (an ('ntr!$"te t' s'me 6!ns '& (an(er.

• I*) '#a))e1 +e'e$t*+s 7 a t)e '& mem$rane re(e)t'rs t#at(an a(t as a gate %#en t#e re(e)t'r (#anges s#a)e. +#ent#e s!gnal m'le("le $!ns t' t#e re(e)t'r )r'te!n, t#e gate')ens 'r (l'ses, all'%!ng 'r $l'(6!ng t#e trans&er '& s)e(!(!'ns s"(# as Na 'r Ca*.



I>. TRANSDUCTION OB SIGNALS• +#en t#e s!gnal re(e)t'rs are )lasma mem$rane )r'te!ns,

t#e trans"(t!'n )r'(ess !s a m"lt!ste) )at#%a. As a res"lt,

t#e s!gnal !s greatl am)l!e s' a small n"m$er '& s!gnalm'le("les (an res"lt !n an e/tens!e (ell"lar res)'nse. T#em"lt!ste) )at#%as als' )r'!e '))'rt"n!t!es &'r m'rereg"lat!'n.

A. S!gnal Trans"(t!'n Pat#%as?• S()a1 t+a)su't(*) $at#&a! – a (#a!n '& m'le("lar

!ntera(t!'ns t#at leas t' a )art!("lar res)'nse %!t#!n t#e (ell.L!6e &all!ng 'm!n's, t#e s!gnal:a(t!ate re(e)t'r a(t!ates an't#er m'le("le, %#!(# a(t!ates an 't#er m'le("le et(. "nt!l t#e)r'te!n !s )r'"(e t#at %!ll )r'!e t#e nal (ell"lar res)'nse –

PROTEIN INTERACTIONS• S!gnal trans"(t!'n means t#at t#e )r'te!ns t#at are

)art!(!)at!ng !n !t (#ange s#a)e an %!t# t#at (#ange !n s#a)et#e a(t!ate 't#er )r'te!ns. >er '&ten, )#'s)#'rlat!'n (a"sest#e (#ange !n ('n&'rmat!'n. T#e 'r!g!nal s!gnal m'le("le !s n't)asse al'ng t#e )at#%a.

. Pr'te!n P#'s)#'rlat!'n an De)#'s)#'rlat!'n?



• Pr'te!n )#'s)#'rlat!'n an e)#'s)#'rlat!'n !s a %!es)rea(ell"lar me(#an!sm t' a(t!ate an ea(t!ate )r'te!ns. Ingeneral t#e en;me t#at trans&ers )#'s)#ate gr'")s &r'm ATP t')r'te!ns are (alle $+*te() ()ase. 'st (t')lasm!( )r'te!n6!nase )#'s)#'rlate e!t#er t#e am!n' a(! ser!ne 'r t#re'n!ne.

• T#e s!gnal !s transm!tte $ a (as(ae '& )r'te!n)#'s)#'rlat!'ns, ea(# $r!ng!ng %!t# !t a (#ange !n )r'te!n('n&'rmat!'n. Ea(# s#a)e (#ange res"lts &r'm t#e !ntera(t!'n '&t#e ne%l ae )#'s)#ate gr'")s %!t# (#arge 'r )'lar am!n'a(!s. T#!s s#a)e (#ange a(t!ates m'stl $"t s'met!mes!na(t!ates t#e )r'te!n.

• T' (#ange t#e )r'te!n $a(6 !nt' !ts 'r!g!nal s#a)e, en;mes(alle $+*te() $#*s$#atases PP are "se t' rem'e t#eae )#'s)#ate gr'")s – e$#*s$#*+!1at(*).De)#'s)#'rlat!'n t"rns ' t#e s!gnal trans"(t!'n )at#%a%#en t#e !n!t!al s!gnal !s n' l'nger )resent.

• A$'"t *J '& '"r genes are t#'"g#t t' ('e &'r )r'te!n 6!nases,s' a s!ngle (ell ma #ae #"nres '& !erent 6!ns '& t#eseen;mes. M!nases a(t!ate meta$'l!( )r'(esses, (ell gr'%t# an(ell !!s!'n.

• T#e )#'s)#'rlat!'nFe)#'s)#'rlat!'n )at#%a a(ts as am'le("lar s%!t(# t#at t"rns s!gnals 'n an ' an are a g''e/am)le '& MOLECULAR REGULATION IN CELLS.

C. Se('n essengers?• an s!gnal!ng )at#%as als' !n'le small %ater:s'l"$le

m'le("les 'r !'ns – se'*) esse)e+s. e(a"se '& t#e!r s!;ean s'l"$!l!t, t#ese m'le("les (an rea!l s)rea t#r'"g# t#e(ell.

• T#e t%' m'st %!el "se se('n messengers are (AP an Ca*

!'ns. A %!e range '& )r'te!ns are sens!t!e t' t#e (t's'l!(('n(entrat!'n '& 'ne 'r t#e 't#er '& t#ese t%' se('nmessengers?

o C!'1(' AMP 7 An en;me (alle ae)!1!1 '!'1ase, !sem$ee !n t#e )lasma mem$rane t' ('nert ATP t'(AP !n res)'nse t' an e/tra(ell"lar s!gnal e/.E)!ne)#r!ne. +#en t#e s!gnal m'le("le $!ns t' a

re(e)t'r, t#e re(e)t'r a(t!ates aenll ((lase t' &'rmman m'le("les '& (AP. T#!s %a 'ne s!gnal m'le("le(an !n"(e t#e snt#es!s '& man (AP m'le("les. T#e(AP m'le("le "s"all a(t!ates a )r'te!n 6!nase m'le("let' )#'s)#'rlate ar!'"s )r'te!ns. On(e t#e (APa(t!ate a )r'te!n 6!nase m'le("le t#e (AP !s ('nerte$a(6 t' AP $ an 't#er en;me (alle$#*s$#*(este+ase. Aenll ((lase (an $e !n#!$!te



$ an !n#!$!t'r G )r'te!n, !& a !erent s!gnal m'le("lea(t!ates a !erent re(e)t'r. an !seases are (a"se$ t'/!ns t#at !ntera(t %!t# t#e se('n messenger ssteme/. C#'lera

'!e? #tt)?FF$(s.%#&reeman.('mFt#el!&e%!re7eF('ntentF(at919F12909:91.#tm

o Ca? (*)s 7 an s!gnal m'le("les, !n(l"!ngne"r'transm!tters, gr'%t# &a(t'rs, s'me #'rm'nes !n"(eres)'nses t#at !n(rease t#e (t's'l!( ('n(entrat!'n '&(al(!"m !'ns. In(rease (al(!"m !'n ('n(entrat!'n (an(a"se m"s(le ('ntra(t!'n, se(ret!'n '& (erta!n s"$stan(es'r (ell !!s!'n. T#!s sstem (an %'r6 $e(a"se t#e n'rmalCa* !'n ('n(entrat!'n !n t#e (t's'l !s a l't l'%er t#an !nt#e sm''t# ER 'r !n t#e e/tra(ell"lar matr!/. A small(#ange !n t#e a$s'l"te ('n(entrat!'n (an res"lt !n a

s"$stant!al (#ange !n t#e (t's'l. T#e release '& Ca !'ns!n'le t#e a(t!at!'n '& 't#er se('n messengers s"(# as!n's!t'l tr!)#'s)#ate IP3. T#e a(t!ate IP3 %!ll m'e t't#e en')lasm!( ret!("l"m an %!ll a(t!ate trans)'rt)r'te!ns t' release st're (al(!"m !'ns !nt' t#e (t's'l.

http://bcs.whfreeman.com/thelifewire8e/content/cat_010/15040-01.htm






>. RESPONSE TO SIGNALSA. Ct')lasm!( an N"(lear Res)'nses• T#e res)'nse '& t#e (ell t' ar!'"s s!gnals ma '(("r !n t#e

(t')lasm 'r !n t#e n"(le"s.• I& !t '(("rs !n t#e (t')lasm, !t ma res"lt !n t#e ')en!ng 'r

(l's!ng '& !'n (#annels 'r a (#ange !n (ell meta$'l!sm.• I& t#!s res)'nse '(("rs !n t#e n"(le"s, !t "s"all tr!ggers t#e

trans(r!)t!'n an translat!'n '& ar!'"s en;me m'le("les $t"rn!ng t#e a))r')r!ate genes 'n. In s'me (ases t#e res)'nse(an t"rn (erta!n genes ' t#at #ae $een a(t!e )re!'"sl.

. B!ne:T"n!ng '& t#e Res)'nse?

• S!gnal!ng )at#%as "s"all #ae a large n"m$er '& ste)s$et%een t#e s!gnal:re(e)t'r a(t!at!'n an t#e (ellKs res)'nse. T#e reas'n &'r t#!s !s t#at t#e s!gnal (an $e am)l!e &e% s!gnalm'le("les (an tr!gger s"$stant!al (#anges !n t#e (ell an t#eres)'nse (an $e er s)e(!( &'r a %!e ar!et '& (ells t#!s !s)'ss!$le $e(a"se ar!'"s (ells %!ll #ae ar!'"s )r'te!ns s' t#esame s!gnal m'le("le (an tr!gger a %!e range '& res)'nsese)en!ng 'n %#at )r'te!ns are )resent !n an g!en (ell



C. Term!nat!'n '& t#e S!gnal• Ea(# m'le("lar (#ange t#at a (ell re(e!es 'nl lasts &'r a s#'rt

t!me. T#e s!gnal m'le("les (an eas!l eta(# &r'm t#e re(e)t'ran t#e re(e)t'r t"rns $a(6 !nt' !ts !na(t!e state -"!(6l. T#erela m'le("les als' ret"rn t' t#e!r !na(t!e &'rm -"!(6l %!t# t#e#el) '& ar!'"s en;mes.

END OB UNIT



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AP Notes on Cell Resp and Photosynthesis