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Ch 9: Water (and nutrients) in
Plants
Simple Diffusion:
material moves from a
location where there is
a high concentration to
a location(s) with lower
concentration, until the
concentration is
“even”.
time
Osmosis:
diffusion of water through a semi-permeable membrane
: higher concentration
of water on the right
(Now this is an isotonic solution)
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In hypertonic solution ->
plasmolyzed cell
In hypotonic solution ->
turgid cell
Imbibition
dry seeds
after
imbibition
Active transport:
Moving materials
against the
concentration gradient
pump
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Water (& mineral
nutrients) flow in
a plant
Contributions by:
Root pressure theory
Capillarity theory
Cohesion-tension
theory
Endodermis:
prevents back
flow & helps with
root pressure
Capillarity:
due to air
pressure
Water (& mineral
nutrients) flow in
a plant
Contributions by:
Root pressure theory
Capillarity theory
Cohesion-tension
theory
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http://www.youtube.com/watch?v=umUn8D6gEOg
Guttation: usually see in early morning
Sugar flow in a plant
Pressure-Flow Hypothesis =
Bulk Flow Hypothesis =
Mass Flow Hypothesis
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Plant nutrients
missing: Si, Ni
Nutrient
Deficiencies
P
normal
K+
S
N
Ca2+
Fe
micros
At the cell membrane: channel proteins
help mineral nutrients move into cells
Mg
At the roots:
(positive ions)
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