Transcript Water and sugar transport & PLANt hormones

Water and sugar transport & PLANt
hormones
OSMOSIS
Which way would the water molecules (red dots) be moving?
Roots
SEM of Marjoram Root
• Mycorrhizae (fungi)
interaction with plant
Mag 100X
What is the significance of increased surface area of the roots of a
plants?
How do plants absorb and transport
water?
 2 methods
1. Root pressure

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
Smaller effect
Usually occurs at night
“push” force
2. Transpiration-Pull
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
Larger effect
Usually occurs during the day
“pull” force
Root Pressure
Root Pressure
Casparian Strip
- __________________
__________________
__________________
- regulates water and
solutes entering xylem
by forcing the “sap” to
pass through
cytoplasm of cells
Xylem Sap
 Maple syrup =
reduced sugar maple
xylem sap
 Collected early
spring
 Only time of year
where xylem
transports sugar to
leaf buds
Transpiration-Pull
• Like drinking from a
straw
• “pulling from up”
effect
• ________________
________________
________________
________________
Did You Know!
A maple tree can lose
on average 220L of
water per hour
during the summer
due to
transpiration!
Cohesion-Tension Theory
Stomata
Cross Section of Dicot Leaf
CO2 enters via stomata for photosynthesis. But water can escape too!
What happens to the sugar?
Translocation
• Translocation – _________________________
_______________________________________
_____________________________
• Movement from ________to _______
– Source: ________________________
• Mature leaves
– Sink: ___________________________
• Roots, shoot tips, fruits
Pressure-Flow Mechanism
Plant Hormones
What are some factors
that affect plant growth?
Auxins
• ____________________
____________________
• ____________________
____________________
• Also trigger formation of
roots, leaves and fruit
(surrounding ovary of
seed)
Seedless Veggies!
Cytokinins
• Promote cell division
• ______________________
• ______________________
______________________
Giberellins
• Promote cell division and cell elongation
• _____________________________________
• _____________________
Increase fruit size, shape and
appearance
Ethene
• _____________________________________
• Used in transporting unripened fruit to
supermarket
• Advantages vs. Disadvantages?
Abscisic Acid (ABA)
• _________________________________
• _____________________________________
_____________________________________
• Promotes dormancy in seeds
After 11 days without
water, the control plant
(left) is dying while the
ABA analog-treated plant
(right) remains healthy.
Homework 
• Section 14.3 and 15.1
• Pg.404 #1-3
• Pg.416 #2,3,5,6,9,17