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What 5 ahfzospheve TheThis plant absoTb^ cwabcY^ frorm^ tme^ 3urYoundiong^ root mfcro envfronment^ ts^ called^ as^ a^ rhfzosphere^
PnGE (^) No. DATE
66 Plant Nater Relatfon
Source of water foT plant
There are four sottrce of cwaker
Huqiascopfc 0ater
The water present around the soil parttctes due o the
adhesfan fox.ce. lhtscoakcr f not avaflable to he plants.
- Cormbfaed cvakez lhe watr piescnt around he oxfdes itke s1lfcen alumtnfom ,et lhe uafey 1 ok avaflable to he planE
(3) ayihattotial CLatey he aater percola ked through he sofl partfcle and
reaches toaiards the grownd water table.
lhts watey 15 not avafla ble_Fo the pant
4Captllaru aater
Ta (^) between (^) 30tpaticle (^) the (^) Srmall (^) gaps (^) are (^) preseat Land they act asa capfllay tuhtch frlled cwTth the
lcuatcr Called a1 capfllaty wacr
Capfllaryaate7 ea3flyayaflable to Fhe plan
Alater_Ls_absolutelye53ernttal^
for Ife
plan cell_or^
tfssue contafrn^ T^
70 aafer.
lhe cwater^ Is_Clnstdexcd_as^
lIxIY Ot^ fe
later: 90-95 Caey. el1xfy of Iife
Frope1ttesi of COater/^ Role^ of^ water hlater fs^ a^ Untyersa^ 30/Vent At (^) room tempenature,f^ Ls^ Fe^ present^
in he^ formform^ oA ot
Itqufd Lhebeflfng^ potat^ eF^ water^ 1s^ very^ high^
t:100C.
Alater has^ htgh^ speciftc^ heat,^ htgh_heat^ ot_fOS1041^ and htgh hat of kapoLuri2abfO E 15 a best transporttng medfuin foT q1530|VeG mineral and tood mater tals. ack as a (^) empera ure (^) stabflfzer IE help tnmatata tngStable ne ba bollfc rate
I 15a raw ma terta for pho tosuynhe sf
Ematntatn (^) trgtd (^) ftsof (^) plant (^) cell help_ (^) tna (^) open (^) ing (^) and (^) dlosing ef Stomata, (^) abscisston Senescernce I (^) act (^) a5 (^) a (^) thermal butter (^) becaUse (^) Fhetr (^) ph (^) s neutral
KWatErabsorbfng organ
Root (^) 1S (^) Q (^) rnafn waCT (^) Qb0Ybtng Tn (^) terrestn (^) fa organ. plant,roOf (^) fS (^) a (^) maln Tn (^) epiphykfcplant absorbfng (^) orqan OTChfds), (^) Fhy (^) have hangtng (^) roofhtseroaE 3pectal (^) ized (ontafn (^) spectalfrzed Wrth (^) the (^) help_0f hts vel (^) amel cellthey (^) absob atrmespherf (^) Cc
velamen CLudter (^) pherfe
al ong Eoth arE^ strongly^ hydrophIlEs- th^ th Thene.Lytcplasin rutoplas^ present^ at^
the
perlphtuategicn,wfth
nucleus. (^) Cell sap VactiolepESent at^ the^ Centte^
contatatngCElLSap
Abs0Iphfonof anter^ bu^ rohs^
ficn
def (^) The ads.oxpkton of batcr^
Tmbtbit fon buhydrophilfc.cornpoundd ts
Calltd mbtbrtioa
nrmbfbtk ton,water^ tstrghbly^ held^ io^
the sufate
Ot_Fhe Coimpournd^ wtthouk^ forrmtng^ a^ clubron.
lhetmbtbftron s tonttrued tril attain_cqutlrbr rm
*Diffuston Solub
vem
of ton, atoms_ar_ molectlles ofrqutd o1g
- (^) frcm (^) the tg (^) ton of (^) htgher (^) concenratfon (^) othe (^) rrgton
edol to (^) the (^) lotULT (^) Concentratton lt tE (^) Qtfatn
Pregure tqutlrbr^ fum
Diffusfon pressure [ D:P):
TE f the potenktal abtlfy o
Fhe soltd Itgutd or gas
to (^) diffuSe (^) from (^) he (^) area of (^15) greakcX
Hhe area Df the Cocentrabroa^ o
louez conctntraten.
he dfffuston p1es5u1e
0f (^) pure (^) water (^) [s
DIffus fon pies5ure always^ more
fs (^) dfeectly
Cf dttfustag pautfcles. proporttonal^ to^ the numbl
Diffustan prtisure
deffct [DPD) B:S
Thc drtference btt een Meyer fr
dfffusfon pres sure
solukton13 caled of pure u
dfiusionpie3ure d efrctt.
(pPD).
suckfon P551e (5P).
pure u tC
Endo osmesi3 hypokondcl5* EXOsm1) Fypevtont Cshs inl)
/ PAGE No DATE
Nowadays tem watey potenbral ts UScd for DPD
*0srnosts
ISa_drff Luston Df uater or solven frorn solutfon Ot louey se (oncen tratton to the solutton of hrghe Conccntrakron hro vgh serntpermeable membranc ts called as a 03mosts.
lypes of 0smosfs
fnd0-0srm1asfs
hlhen plant cell keptfn_a solubfon hayrng locuey
solute concentrabton LhypoFon tc
Asa LesLltDuter solubrom lhupot onfc) mDve fnsrde he
cell (^) through (^) sermtpexmcable (^) mtunbrane. (^) and se cell
cutoplasrm betom Fugid. 1s alled asendo Os rmosfs
FxD-0310031s eversfble) alhen (^) plan (^) cell (^) kep (^) rn (^) a (^) s0lubton havtng (^) hghe 40lute (^) con.centrakron (^) Lhypez fonfc (^) as a (^) resulE
fnney khe
6LtesolutrornLhyperonic moves Ousfde he cell throvghsemtpexntable (^) membraneE (^) cell (^) cytoplasm betome (^) lacctd (^) fs (^) nown (^) as (^) AD-O (^) 3Ynosfs
Plasrmolusts EXO-05 rnos 1s but frevers tble
hlhen plan cellkep faa r0uch more
hyper (^) tonic (^) solutfon htle (^) foner (^) cell (^) sap (^) cQncentrabton fs (^) hypotonfc O.s (^) a (^) result (^) fnne (^) 30luEton nove (^) 0utsfde (^) threvgh strmtpermeable (^) membrane (^) fscalled (^) plasmoly3is The (^) cell_ (^) cqtoplasrn fa perymanenbly (^) s (^) hrtnk (^) and darnaged Tt (^) s a (^) +9pe of (^) exo-0sun (^) es 1s.
PAGE No DATE
gfn k
na ge Factlttated^ drff cus forn
n_thtsyp of drffuston, the absaptfon of solute
Carifec Dut hhrD vgh bhe medtatd chiannel 3uch as cel mernbiane. efa_no_ tnerg y fs requfred. (wthout expendihure of energy n (^) cel (^) membrant (^) he (^) medra bed (^) chanmel (^) s (^) aPTOtein rmole culles Qutet sfde of cel
atpid
bilayer 2/i7 Protefm
A A
Cyroplas
|later potentral ):DPD
lhe ktnetfc ernergy posses5ed by he
molecules (^) fs (^) called chermtcal (^) potenbia (^) andhe (^) chern (^) fcapokenttal of (^) wabec
fs calltd as^ waleY potental.
The (^) water_potnkfal (^) DF (^) pUTe (^) Cabey
ak noraal termpe rature
andanrrnal prestU Te (NTP fs zero
lhen Solute added the uatey
potenbtal (^) decrease (^60) Fhat
fns fde he planb (ell and
solubrO Cate pofen ral fs
neqatt ve HThe (^) water (^) po~ernttal (^) deno (^) jed bq (^) greek (^) symbol (^) fsT (^) (P Ihe (^) twater (^) aluways (^) flou from (^) less (^) heqatrve (^) (ua (^) ica potcnttal (^) to (^) the ooYe (^) neqatfve (water (^) potcn~fal.
PAGE No. DATE
Facto affectn the^ cwabey^
potenttal
UTshce of^ Captllary^ ajate^
fs ien^ bral
0 wa^ bey_absorpt
ton fs^ axfmum_
0t 50f
FCmpeyature bebwcen^ 20'Cto^30 C^ Cwatereduces ne
(t11JEEfgh_concentratforof^ solutes^ fn^ 40L^
aze Caures
taic_oE absoaptfon^ f^ wate (Mfoorlu acratcd sotl^ shows^ po0r^ abso7pEfor^
Tdte.
(V (^) Tncreased ranspfratforn accelexatesFhe^ ydbe^
of
absCphfon of uwater^ fn^ he^ fufgaked1ptL
Path Of water across he toot TACco.rdtng o the F-muchwater move from Fhe sot|
o too hatr, coxtical celLendodeamispexfccucle and
ffnally th reachts tOcuards bhe xylem through fwO Cuaus
Apoplast pathwau
SLrmplas pa~hwau
The move rnent Of aater takc
place (^) exclusfvely (^) through
)Apoplast pathtuzay
the (^) cell (^) wall (^) and (^) tn~ecellulay spa.ce
lhis mo yemeht fi a non-
05mo bic and O CC due to
he imbtbthton. The (^) cellu (^) los fe (^) materfal
p7esent on Fhe all
Lcell_are (^) srongly of^ varfous hydrophtl (^) fC (^) ahd tuater (^50) Fhat pexmeable^ to^ the waftx (^) nnDve (^) thrDLugh Fhen
3ap wea^ k^
nineras^ salb^
peerut ih^ plant^
cell.
(sugarcant^ y'utce^
) PAGE^ No DATE
ed bs he
AteoTd (^) fag to^ this^ theory,^
the water^
abs0tbed
plant o0t^ wttth^ the^
help Df^ osrmotfc^
gradfen
The osYmotfc
a epffom ell_o gadtent^ help de velop^ PPP
LDletala to_pea^ fcucle.and^
this psmotfc^ qrad^ fer TOLneanslocatto of^ water^
because_IE_dEyelop
hydrauska fc_pre5su^ re^ root^
pressure) whtch^ help^ for^ the
ASCent^ of^ sap.(weak^ rn^ fnera^ ls^
salbsPiesent Tn^ fhe^ plant
cell) ACCOTdtng to this^ theorq,^ bhee^ fs^ n0^ dfrcctlg^
requtre
theexpfn di ture of energy.
bNon051motfc absonptfon 1Ecwas proposed by 1sramey and Thtmann ACad tng n this heou, he waker abs oub from the plant To0 from he soT aqafnsy concenzratfon gradrent. Ihere fs (^) a (^) dfeckis (^) expend fture (^) of (^) enerq (^) takes placc.
The lower tempeiatuLYe he poor Supplu Of
Oxugen
Ieduce or refarded the_atey uptake
2 a15fve absorpk fon:
Tn pass fve abso1pt fon he
livfng oo cell do not play
an fmpoyt ant role fn
absorphfon
Tnpasafye (^) olbs (^) 01p~fon, ~he deftctt (^) and (^) draw (^) water franspratton^ deve (^) lop (^) ok fro (^) petfole
oo StermSterm anaand
The
transpiiafonaevelop (^) suCFfon (^) torCe HransmtHed (^) fronm_aeiial whfc^ fs par (^) of (^) the undexqround plant (^) to (^) he ro0r_TOLFOe_dbsoipkfon (^) 0f (^) watez.
nl hat |s sqp? TheToTm awaca^ piesen t^ in^ +he^ plant body^ tmntthe of wcdk^ soll of mineral (^) sal
PAGE No. DATE
Translo catfon of_uaier AscentOf sap lhe (^) opumard (^) movement of (^) tuater3ap
tom too
FO (^) Fheaerfalpart (^) 0f (^) the (^) plants
agafnst qraviy
(alled (^) rans (^) locafe (^) of wat er (^) or
a3cenb O saP
aRoot (^) pres3ure (^) Theory Vrtal (^) The o) Thfs (^) the (^) onq wa.s (^) prop ased (^) bu (^) T (^) hfestly Accondtng to^ thfs (^) theory,the (^) hydraust
atfa pres s01e
developfa^ the^ lfving root (^) celle rootpress1e help (^) fo
he ascent of SCp
Alhen te khe stem of well watex plant
fs Cut afew
centfmeher above (^) the (^) sorl (^) level, (^) here (^) fs a of exudation aatex (^) (sap) (^) ocLL (^) Fhroughihe (^) xqlerm roof pessure due^ to^ the In (^) plants, (^) Hhe (^) roo (^) pressture fstl (^) tot2 (^) bar (^) developeol and (^) thfs root (^) pTessureInfting (^) he
mettes OaterLupto^ lD^ to^20
ROot (^) press (^) urefsfsfnfLuenced (^) bq Femperature (^) of (^) sofl, OAggen, (^) rmofsiure3alatnerdl contents (^) et (^) u
/ PAGE No DATE
Limttatton0bjeckton Capfllary effecE ts 0nly appl teable uhen the capfllary afrectiy dep (^) tntp Fhe (^) d (^) solution. But (^) fn (^) planbS, (^) IE rs (^) not (^) p0s5 fble. Lne_aramtfer _of CaptLlarq equ fre vers narrocw (5mallex) HO@eyeY,in talley plant, xylerm ve33e raVfng wIaer umch
for the _captllary effect, vesscls mus7 be ContfmUous
andcomplefely hol low from one end to the ofher
But end
fn 30me1 5Closed.
Pl&ces
TLnn03pexmplant are^ the (^) tallest (^) plant (^) fa the (^) cookk but (^) hey (^) does (^) rnot (^) po55t33 (^) ve3sel s
kiLoheston (^) tensteq (^) hecoTy (^) lranspfratton
pull heory)
In (^) 18q4DIxon (^) and (^) Jolly poposed (^) bhe (^) transpfrabto
pull Fhe.ory.
This (^) theory (^) fs (^) wfdelu (^) acepred
heory.
lhts thepry based on marn
three (^) pitncIples 1Cohes (^) fon (^) 0f (^) ater (^) Ihe molecules (^) fs attTactfombe^ fweer^ sfntla
called coheston. force.
In betueen wdtey mole ccoleg
e, sTonq cokhes torn fotce
fspIesent
he coater molecules Cannot
The Separate^ east^ lu
coes ton be force ber
350atms waber^ rmolecales^5 dbout
2Adhesfon_o 2ater +The (^) atttactton (^) berween disa (^) fmflar (^) molecule3 (^3)
adheston force Called
In (^) plant (^) the (^) attractton tonbeFl Catty (^) mole culeg (^) an
lg Xqlem^ Lells^
deyelop adhestonIOZCE
el op (ontinue Lnt_adhestom and^ coheston^
forCe_help0-aevelop ont
Czater colurmn
Lrarlspfratfon^ fs^ evaporatton^
ot (^) Wa FeTfom^ the
nertalpart of he plant
3 Transtpfration pull
The tanapfratfon^ deyelop^ tenstonn^ pres3UIe^ bo@^2020 atrmatm ahd fhfs^ p^ tenstpn_^ press^ ure^ rans^ rmUf^ ted^
from pebfole
FD SFe m and stem fo rOOFS t help^ to^ ma^ fn^ tafn^ contt^ nuovs^ Uate^ (olunn.
For the ascent of sap ad hesfon cohesfon and bransphatin
a20Tk ogeher
Obie (^) cEfon/ (^) Ltmi (^) tatton'
Due to (^) he (^) variatfon (^) tn eraperafure (^) durtrng (^) day (^) and ntght (^) rme (^) mau (^) develop (^) afr (^) bubble which (^) rmay (^) bTeak the (^) conttnufFy (^) o (^) wabex (^) (olumn. Ascent (^) of (^) 50p (^) also (^) eb Observed (^) tn (^) eict (^) decduous These (^) planbs (^) shed planw
hhefr leaves
This (^) mnechantsm assume (^) Fhat (^) rachetds han (^) vessets (^) as are^ rnore (^) effelefficlent hefr (^) end (^) dal (^) suppoi waterCuater^ columncolurmn.
quttatioroENo lhat fs hta Hhods^ fwatcy^ sto DATE maba) T5 dpecfaltsed^ struture^
through vhfchg (^15) OCCU 15 called hydathed^ or^ chalk^
glarnq
Tmp lrih^ sh01e^ nobe^ on^
much hYPO
ateral ranslocat ton 5 observed^ tn^ the^ toot^
and stCIN_ Qenli radial transtocattorn,the^
t[anslocation OF^ fopDd
OCkur from phloerm^ p^ pffh he fang.ential^ ttanslocatfo^
0t foocfTem phlber
CorkX reqio
em
,PiFh Lairallhe transpoy^ of^ food^ occurfn^ bfafrecpfoa
Mechantsm ot sugar iranspor thre Lgn phlocm Ihe munch thepry_Dr hyppthesis she mosf (onvincing LxpEriment to Lxplatn about sugar Franspor throuah the phloerm
(onvinCing
Concena/e Vaar sa|n Drlute sugay
afeY
ACLOTdfng (^) to (^) thls (^) iypofhests, qrad fhe^ turger^ pressure^ exts tent (^) exfst (^) betueen 3upplu (^) 40uTCe (^) end (^) to consumptto.n end (stnk the The (^) organic (^) 5o (^) ute are (^) carrted dtrectton (^) of (^) the posfbively^ fruthe (^) posttIve qadfent (^) ahd (^) ~he organtc (^) food (^) ocLLr transl^ pcahton (^) of FhrOghihe (^) phloerm f (^) htgher Conch (^) 0_ (^) Fhe Prom (^) the (^) reqrot regfonOf (^) ourr cond
req fon
Alhat t6 guttabr on? The loss (^) of (^) wate fn the (^) form of (^) lfgufd The ex Udatton of wakey occuY throug h fhe fntake (^) part. 1s (^) called as (^) guafton.
PAGE No DATE mp
Transpf ratron
IEeekaporatto0 of^ water from the aer tal pajt ot the
plant (^) fs (^) Called (^) as (^) transpfratfon Near (^) abotu (^) 95% (^) waker (^) l03s
throLLQhthe tran3pfiatio
prOces flhe (^) ranspfrahton (^) rmostly (^) occLeT
through leaves
pes Df tanspfratton
Cuttru (^) lar (^) transptratron (uttcle fs a (^) uOxy (^) laqer_prestnt (^) on
fhe epideaunts 0f the
plant par lhecutfcle (^) reduce (^) the hanaptrakton_ratc (^) but (^) 5tfl 1-10 (^) Df (^) aater (^) s (^) l0st (^) through as Cuttcular ~anapfratton the^ Caffcle_fs^ (alled cuHee Rlder
entfcu lar bTansptratron
he leaticlrs are the fime
pores presen 0n0n fhethe olderolder
part of the plant such as
bark of the old sterm and
perfcarp Of wO0dy fruft
lhrough (^) thts (^) lenttcles0 (^) fO
form atez^ fs^ lost^ fn^ the
0P_water (^) VapouS (^) fs (^) called Cutie le lenbfcular^ rans^ pirat^ ton. Tentire
Fpiderrmis
Mechantstm 0P ppentng and losfng of somata
In 197H, Leyttt proppsed the protompurmp rmectran tsra
for the openrng and costmq fstomata
Forthe opentng and clastng of stomata,achfve transpot
of k 1on fntoe_ qaurd cell and out of therm
Durtng dautimestarch fs L0nveited fato malitc actd fathe cytoplasm of the gaurd ell. I (^) drssoctate H (^) fon_and malate_fon. fnto (^) the outex
subsfdfary cell- cohile k fon enter fnto fhe gaurd
Tell
As a result 03motfc poentfa of Fhe qaurd cell frcrase
and oabey from he sunrocu nd f ng cell enter_rato the gaurd cell
he gaurd cell_becorme fully furgtd
FTheouter thtn Call stre~ch and frner thtc k cuall pulled
apart and stomata rCLmarn open Cfom mathafn the k fon balance.
H
malala on
Open stomafa
DATE
Dring ntghtbime^ the^
(DLoncenttieinInfr^ thethe^ aa.qaur
actdic fn the Lell_fndease and^ the^ qaurd^
cell pH^ become^
Inthe
pIPsence oP^ Co^ and^ ABA^ (Abs
ic actd).
tnhtbtt the^ uptake^ of^ k^
fon and^ fon
AS a^ esult,^ kT^ and^ (^ fon^ As a L5ulE move^ Out^ rough^ to^ the 3ub1fdtaiq^ celland^ osrmotfc^
cOnc_OF qaurd^ elldecTease.
hewater^ move^ out^ exo-^ musts^ and^
ga urd^ cell^ becoma The
5ubifdfaru (^) cell beCome
flactd Lnnerwall_oP^ gaurd^ cell^ Come^ fn^ (ontat^ wh^ tah other and stomata closed.
au
closed somaa
