SOLUTE TRANSPORT Flashcards
Guard cells
K+, malate, sucrose
responds to blue light
Stomata
open- turgid
closed- flaccid
Guard cell opening
lower solute potential
decrease water potential
water uptake
stomata open
Guard cell closing
solute potential increases
water potential increases
water loss
stomata closed
Ficks first law
diffusion
movement of molecules or atoms from a region of high concentration to low concentration
Chemical potential
the sum of the concentration, electrical and hydrostatic pressure
Simple diffusion
without transporter
Facilitated diffusion
involved in the movement of specific molecule
needs specific channels or carrier proteins
needs no ATP energy for its transport
glucose permease
glucose transporter
chloroplast inner envelope
TPT
passive counter-exchange of Pi or triose phosphate
electric field
balances the concentration gradient in activity of “i”
active transport
ATPase, symporter (same) and antiporter (different)
H+ pumping ATPase (blue light)
influx/efflux
- 1 -200 (active)
1 0. -50 (active) - 0 -300 (passive)
passive vs active
low affinity K+ transporter (channel/passive)
high affinity k+ transporter (symporter/active)
non–reducing sugars
transported via phloem
sucrose
pigments
etioplast- no chlorphyll
proplastid- undifferentiated, colourless
amyloplast- starch storage
conversion from etioplast to chloroplast
light induces conversion
400-700 nm
Sink
non-photosynthetic developing
organ or an organ that does not produce
enough photosynthate
solute potential high, low turgor pressure
Source
Exporting plant tissues or organs
that produces photosynthate (e.g. sugars)–
mature and photosynthetically active leave
solute potential low, high turgor pressure
mature sieve elements
no nucleus
sieve tube
functional units for long distance translocation
Source-sink transition leaf
mature and immature parts
leaf base: source
leaf tip: sink
