Chapter 9 - Water in plants Flashcards
What is transpiration?
Moves water from roots to leaves
What is translocation?
Moves sugar from leaves/photosynthetic tissues & storage organs
Shipped to where carbs are needed
From “sources” to “sinks”
What are the 3 levels of transport?
o Cellular level
Uptake of water/solutes by individual cells
o Short distance
Transport of substances, cell to cell
o Long distance
Sap movement via xylem/phloem for whole plant
What is aqueous solution in the xylem?
Xylem sap
LATIN:
Ton
Tension
LATIN:
iso
same/equal
LATIN:
hypo
below/reduced
LATIN:
Hyper
above, elevated
What is isotonic osmosis?
No net movement, the levels are constant but water is moving
What is hypotonic osmosis?
Water moves into the cell to dilute the solution equally
What is hypertonic osmosis?
Water leaves the cell to dilute the solution equally
What is osmosis?
Diffusion of water through a semipermeable membrane
Which ‘hesion?
o Attraction between like molecules
o Cohesion of H2O due to H-bonds
o Underlies surface tension
Cohesion
Which ‘hesion?
o Attraction between unlike molecules
o Water attracted to charged surfaces
o Underlies capillary action
Adhesion
What is the most accepted mechanism of water transport?
Cohesion-tension theory
o Due to diffs in physical pressure
o Can be positive or negative pressure
Potential pressure
o Due to diffs in solute concentration
o Creates osmotic pressure
Osmotic potential
Water transport 3 steps:
Absorption of soil water by roots
Ascent of xylem sap up stele
Movement into leaf and out stomata
LATIN:
myco
Fungus
LATIN:
rhiz
root
LATIN:
Sym
together/with
What route is with the cytoplasm
symplast
Which route is away from the cytoplasm?
Apoplast
