Transcript WATER

WATER
MOLECULAR MOVEMENT
• A LIQUID IN WHICH A SUBSTANCE
DISSOLVES
• SOLVENT
• WATER
MOLECULAR MOVEMENT
• NATURE ADORES BALANCE
• WIND
• HOT AIR MOVING TOWARD COLD AIR
• WICKING
• WATER MOVING FROM WET TO DRY
MOLECULAR MOVEMENT
• MOVEMENT OF MOLECULES FROM REGION
ON HIGHER CONCENTRATION TO A
REGION OF LOWER CONCENTRATION
• DIFFUSION
• MOVING FROM HIGH TO LOW
• ALONG THE DIFFUSION GRADIENT
• MOVING FROM LOW TO HIGH
• AGAINST THE DIFFUSION GRADIENT
MOLECULAR MOVEMENT
• MOLECULES EQUALLY DISTRIBUTED IN SPACE
• EQUILIBRIUM
FIG. 9.2B
FIG. 9.2C
MOLECULAR MOVEMENT
• MEMBRANES THAT ALLOW MOLECULES
TO PASS THROUGH
• PERMEABLE, OR SEMIPERMEABLE
• PLANT MEMBRANES ARE SEMIPERMEABLE
MOLECULAR MOVEMENT
• NATURAL MOVEMENT OF SUBSTANCE
FROM ONE SIDE OF A MEMBRANE OF
HIGHER CONCENTRATION TO THE
OTHER SIDE OF LOWER
CONCENTRATION
• OSMOSIS
• WATER ENTERS CELLS VIA OSMOSIS
MOLECULAR MOVEMENT
• THE PRESSURE THAT WOULD BE REQUIRED
TO STOP OSMOSIS
• OSMOTIC POTENTIAL
• THE PRESSURE THAT DEVELOPS ON THE
INSIDE OF THE CELL WALL
• PRESSURE POTENTIAL
• OSMOTIC POTENTIAL + PRESSURE
POTENTIAL
• WATER POTENTIAL
• THE ABILITY OR A SOLUTION TO DRAW
WATER TOWARD IT
• THE MORE SOLUTES, THE HIGHER THE
WATER POTENTIAL
MOLECULAR MOVEMENT
• PURE WATER
• HIGHER WATER POTENTIAL
• WATER WITH MORE DISSOLVED SALTS
• LOWER WATER POTENTIAL
• SOLUTE POTENTIAL IS
ANOTHER NAME FOR
OSMOTIC POTENTIAL
OSMOSIS
• ISOTONIC
• WATER POTENTIAL SAME INSIDE AND OUTSIDE
OF CELL
• NO WATER MOVEMENT
OSMOSIS
• HYPOTONIC
• WATER POTENTIAL LOWER INSIDE CELL
• MORE SOLUTES INSIDE CELL
• WATER MOVES INTO CELL
OSMOSIS
• HYPERTONIC
• WATER POTENTIAL LOWER OUTSIDE CELL
• MORE SOLUTES OUTSIDE CELL
• SALINE WATER
• WATER MOVES OUT OF CELL
MOLECULAR MOVEMENT
• TWO ADJACENT CELLS
• ONE WITH HIGHER WATER POTENTIAL MOVES
WATER TO THE ONE WITH LOWER WATER
POTENTIAL
• WATER IN SOIL HAS HIGHER WATER POTENTIAL
THAN WATER INSIDE ROOT CELLS
• WATER MOVES FROM SOIL INTO ROOT CELL
MOLECULAR MOVEMENT
• SALT-CONTAMINATED WATER HAS
LOWER WATER POTENTIAL THAN
ROOT CELLS
• WATER MOVES OUT OF ROOTS
• PLASMOLYSIS
MOLECULAR MOVEMENT
• THE ATTRACTION OF WATER INSIDE ROOTS
• OSMOSIS
• IMBIBITION
• WATER ATTRACTED TO CHARGED PARTICLES
INSIDE ROOTS
• THIS IS NOT OSMOSIS
• SEEDS SWELL WITH GREAT FORCE
• LENTILS BREAKING BOX (SEED COAT)
MOLECULAR MOVEMENT
• ROOTS EXPEND ENERGY TO PUMP WATER INSIDE
PLANT
• ACTIVE TRANSPORT
• WATER AT TIPS OF LEAVES IN MORNING
• GUTTATION THROUGH HYDATHODES
• NIGHT TIME
• NO TRANSPIRATION
• ACTIVE TRANSPORT SATURATES PLANT UNTIL
PUSHING OUT TIP
TRANSPIRATION
• MORE THAN 90% OF WATER EVAPORATED
THROUGH STOMATA
• CORN PLANT TRANSPIRES 4 GALLONS A WEEK
TRANSPIRATION
• WATER MOVES THROUGH XYLEM BY
ATTRACTIVE FORCES
• COHESION
• WATER MOLECULES ATTRACTED TO EACH
OTHER
• TRAIN
• AS WATER MOLECULE EVAPORATES OUT
STOMATA, PULLS THE TRAIN THROUGH THE
ROOTS
FIG. 9.10
WATER MOLECULES
• COHESION
• WATER MOLECULES
ATTRACTION TO EACH OTHER
• ADHESION
• WATER MOLECULES
ATTRACTION TO SURFACES
TRANSPIRATION
• OPENINGS ON BOTTOM OF LEAF
• STOMATA
TRANSPIRATION
• GUARD CELLS OPEN AND CLOSE STOMATA
• CONTROLS TURGOR PRESSURE WITH
POTASSIUM IONS
• ABSORB K
• GUARD CELLS SWELL WITH WATER AND
OPEN STOMATA
• DEPARTURE OF K
• GUARD CELLS SHRINK AND CLOSE
STOMATA
TRANSLOCATION
• SUGAR (FOOD) PRODUCED IN LEAVES
• HIGH CONCENTRATION OF SUGAR
SOLUTION
• SOURCE CELL
• SUGAR (FOOD) SOLUTION MOVES TO
LOWER CONCENTRATION CELLS
• SINK CELLS
• ROOTS
• STORAGE CELLS