The simplest ORGAN
ORGANSORGANS - have
one or more FUNCTIONS and composed of SEVERAL TISSUES
ROOTS are the simplest
FUNCTIONS of ROOTSANCHORAGE
FUNCTIONS of ROOTSABSORBING and
CONDUCTING Water and Nutrients
FUNCTIONS of ROOTSFOOD STORAGE
TaprootsFascicled roots
FUNCTIONS of ROOTSFOOD STORAGE in Cortex
FUNCTIONS of ROOTSAll ROOTS are for:
AnchorageAbsorbing and
Conducting Nutrients
Food Storage
Some can REPRODUCE by root cuttings
CLASSIFICATION of ROOTSBased on
ORIGINATION
PRIMARYSECONDARYADVENTITIOUS
CLASSIFICATION of ROOTSBased on TYPE of
ROOT SYSTEM
TaprootFibrousFascicled
ROOT ANATOMYRegion of
Maturation (Differentiation)
Region of Elongation
Meristem Region
Quiescent Zone
Root Cap
ROOT ANATOMYDicots
ROOT ANATOMYMonocots
ROOT ANATOMYSecondary or Lateral root generation
ROOT PHYSIOLOGYWater and Nutrient
CONDUCTION is comprised of THREE ACTIONS
ROOT PRESSURECAPILLARITYTRANSPIRATION
ROOT PHYSIOLOGYROOT
PRESSURE
OSMOSIS
Pathway A – Intercellular Spaces
Pathway B – Root Hairs
ROOT PHYSIOLOGYROOT PRESSURE
Casparian Strip
ROOT PHYSIOLOGYCAPILLARY ACTION (or Capillarity)
Adhesion Cohesion
ROOT PHYSIOLOGYTRANSPIRATIONAL
PULL (or Transpiration)
As WATER EVAPORATES or DIFFUSES from the surface of a leaf, and as cells replace water , the continuous loss of water PULLS it up through plant
SPECIALIZED ROOTS and ASSOCIATIONSPROP ROOTS
CLIMBERS
PNEUMATOPHORES
SPECIALIZED ROOTS and ASSOCIATIONSEPIPHYTES
CONTRACTILE ROOTS
PARASITIC ROOTS
ROOT ASSOCIATIONSMYCORRHIZAL
Associations”Fungus Root”MUTUALISTIC
fungus/plant relationship
Helps absorb WATER and NUTRIENTS for PLANT
Plant provides SUGARS for FUNGUS
ROOT ASSOCIATIONSMYCORRHIZAL Associations
ROOT ASSOCIATIONSBACTERIAL Associations
MUTUALISTIC bacterial/plant relationship
BACTERIA absorbs NITROGEN from atmosphere, and converts it into AMMONIUM (NH4
-) a NUTRIENT for PLANTS
PLANT provides SUGARS for BACTERIA