Gas Exchange And Trasport In Plants Flashcards
Molecules that cross easily over the lipid bilayer
Hydrocarbons, CO2, O2
Main electogenic pump of plants, fungi and bacteria
Proton pump
Diffusion
Particles spreading out unto the avaliable space
Transport protiens, types and what travels through them
Channel protiens - small changed things (water and things with +/-)
Carrier protiens - bigger things
Area of more condensed substance to area that is less condensed
Concentration gradient
Passive transport
No energy spent
Simple diffusion - through membrane
Facilitated diffusion - through protien
Tonicity (3 types)
Hypotonic
Isotonic
Hypertonic
Plant and animal cells reactions to different tonicities
Hypotonic, isotonic, hypertonic
Lysed, normal, shriveled
Turgid, flaccid, plasmolyzed
Dried it plant cell, membrane pulled away from wall, phenomenon called…
Plasmolysis
Stomata
Pores for gas exchange, guard cells open and close
A leafs ground tissue is called
Mesophyll
Leaf anatomy layers
Upper epidermis
Palisade mesophyll
Spongy mesophyll
Lower epidermis
Palisade mesophyll
One or more layers of elongated parenchyma cells
Spongy mesophyll
Losely arranged parenchyma cells, air gaps for oxygen to circulate around.
One plant adaption to limit water loss
Thick cuticles
Attributes of guard cells that facilitate them opening
Connected only at tips
Unevenly thickened cell walls (thicker in the middle)
Cellulose microfibrils arranged radialy
Stomata opening mechanism
Proton pump pumps H+ out of cell
K+ flows into cell
Enough K+ goes in that water follows by osmosis
Stomata are generally open…
During the day
Cues for stomata to open
Light, little CO2, internal clock
Apoplastic route
Route water and minerals take into roots.
Travel in cell walls and in the space between cells
Symplastic route
Route for water and minerals into plant root
Travel through the symplast (cytosol and plasdemosmata of cells)
Things water and minerals must pass to get into plant (symplastic order)
Cell wall, plasma membrane, cytosol, epidermis, plasdesmosmata, cortex, endodermis with casparian strip, vascular cylinder, into xylem
Last boarder check for water and minerals
The endodermis with the casparian strip, must enter cytosol to get past.
The water and minerals in a xylem is
Xylem sap
Transpiration
Loss of water vapour from leaves
Root pressure
Water flowing in from the roots into the xylem
Cohesion-tension hypothesis
Transpiration pulls the xylem sap up
Cohesion and adhesion, what are they
Cohesion - hydrogen bonds between water
Adhesion - hydrogen bonds connecting water to cell wall
Translocation
The transport of photosynthesis products
Sugary solution in sieve tubes
Phloem sap
Sugar source and sugar sink, what can be both?
Area of net production of sugar (mature leaves)
Area consuming sugar (areas of growth)
Roots store sugar, can be source and sink at different points
Phloem sap is moved by
Pressure flow. Uptake in sugar means uptake in water means higher pressure, pressure pushes sap towards sugar sink that has lower pressure
