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Transport in Transport in PlantPlant
Water transport
Food Food transporttransport
Water TransportWater Transport
Root PressureCapillary actionTranspiration
Root pressureRoot pressure
Water is drawn in root by osmosis. Excess water is pushed into xylem by pressure. This pressure push water up in xylem.
Capillary ActionCapillary ActionSince the adhesive force between water molecules and tube materials is larger than cohesive force between water molecules, water column is pulled up by adhesive force.
TranspirationTranspirationStomata opened by guard cells. Water diffuse out through stomata.Water evaporate from cell wall to
intercellular space.Water draw to surface cell from
xylem by osmosis.Unbreakable water column pull up
by leave.Water draw into xylem from root
cell by pull.Water draw from soil to root cells.
StomataStomataGlucose increase
Water diffuse outWater diffuse outSymplast, apoplast
Diffusion evaporation
Xylem Xylem
TracheidTracheid
Photo Photo
In root In root
In RootIn Root
Water pathwayWater pathway
Casparian stripCasparian strip
Mature endodermisMature endodermis
Photo of young Photo of young rootroot
Model of Model of transpirationtranspiration
Potometer Potometer Not for rate of transpiration but for water absorption only. How can transpiration rate be determi
nated.
Plant in dry regionPlant in dry regionIncrease water absorption
Decrease water evaporation
Transport of food Transport of food in Phloem in Phloem
CriteriaEnergy requiredOccurred in sieve tubesDirection from leave to
organsUp and down possible
Structure of Structure of phloemphloem
Mass flow Mass flow hypothesishypothesisi. Sucrose move to phloem from leave cell
by active transport.ii. Water potential in phloem decrease.iii. Water move in phloem by osmosis.iv. Water volume increase in phloem,
turgid pressure increase.v. Sucrose remove from phloem at organ
by active transport.vi. Water potential in phloem increase.vii. Water move out of phloem by osmosis.
Pressure decrease.viii.Water flow by pressure difference.ix. Sucrose flow with water along phloem.
Model of Model of translocationtranslocation
Experiment Experiment