Transport in plants Flashcards
Three levels of transport in plants
Uptake of water by indiv cell, short distance, long distance
Short distance transport
Cell to cell
Long distance transport
Sap in xylem and phloem
Two types of transport in cellular level
Passive, active
Enable plant cells to maintain an internal environmental difference from their surrounding
Specific transport proteins
It occurs when a solute molecule diffuses across a membrane due to presence of concentration gradient; no direct expenditure of energy; ex: diffusion and osmosis
Passive transport
Happens when there is unequal concentration (greater to lesser)
Diffusion
Diffusion of water through a semipermeable membrane
Osmosis
Occurs when a solute molecule is moved across a membrane against the concentration gradient; expends metabolic energy; ex: proton pump
Active transport
Active transporter in plants
Proton pump
Movement of fluid due to pressure or gravity differences
Massive/ bulk flow
Diffusion that causes swelling
Imbibition
Types of osmosis in a cell
Turgid, flaccid, plasmolyzed
These control opening and closing of stomata
Guard cells
Closed stomata
Flaccid
Open stomata
Turgid
Three routes water and minerals can travel through
Out across and into a cell, apoplast, symplast
Passes through the cell wall
Apoplast
Living part of tissue; plasmodesmata
Symplast
It is for water retention and control
Casparian strip
Long distance movement that allows water to move up the xylem
Bulk flow
Long distance movement depends on:
Transpiration pull, cohesion & adhesion, capillary forces, strong cell walls
The transpiration cohesion tension mechanism
H2O was pulled up by negative pressure, water vapor in airspaces diffuses down its water potential gradient and exits stomata
Breaks chain of water molecules
Cavitation
