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Vascularization - Coggle Diagram

- - - - Xylem (Tracheids) Main Function: Water Transport
      - Phloem (Sieve Tube Element/Cells, Companion/Albuminous Cells) Main Function: Photosynthate Transport
  - - - Euphyllophytes had an independent evolution
    - - High atmospheric global temperatures, Low stomatal densities, Low capacities for water uptake prior to root evolution, Lacking efficient vascular transport in leaves
    - - Liverwort gametophyte, Moss gametophyte, Lycophyte sporophyte, Monilophyte sporophyte, Sperm sporophyte
    - - Evolution of Euphylls
        
        Planation (Flattening of axes into 2 dimensional
        
        Webbing (Develop thin tissue between axes of branches, branching becomes veins, webbing becomes mesophyll)
        
        Overtopping (Unequal branching)
- - - - Found only in sporophytes of vascular plants. Functions: Anchors plant body to substrate, absorbs water & dissolved minerals
      - Apical Meristem (Quiescent center, rarely divides, maintains initial cells, behind root cap)
      - Root Cap (Evolved independently, protected underlying tissues, Secrete mucilage)
      - Pericycle (Pluripotent, initiation of lateral root development, just inside the endodermis)
      - Root Hairs (Single celled, Major absorption of water and minerals via osmosis from hypotonic soil solution to hypertonic cells, delicate, short lived)
      - Cortex (Large storage area, outermost layers may show, hypodermis & exodermis; casparian strip & suberized lamella, bound by endodermis and epidermis
      - Endodermis Casparian strip, prevents apoplastic movement of water, forces water to move through cell membranes to be filtered)
    - - Lateral Roots (Adventitious roots, derived from stems and leaves, dominant in eudicots) Seminal Roots (Derived from mesocotyl)
      - Primary Root (Derived from Radicle, Main root, dominant in eudicots, ephemeral in monocots)
- - - - Water evaporates out of open stomata to drier atmosphere, creating water potential differential
        
        Water potential from mesophyll cells all the way back to xylem draws water from vein
        
        Water enters through root hair via osmosis due to hypotonic soil solution
        
        Water passes through endodermis, filtering solution, preventing embolism and foreign invaders
        
        Water is pulled up stem, under tension, in an unbroken column, water remains unbroken due to the cohesion of water molecules
  - - - Photosynthate is loaded into sieve tube elements with help of companion cells from source (sugars transported as sucrose, transported into sieve tube elements, decreases water potential of STE)
        
        Increases osmotic concentration, decreases water potential in sieve tube (Creates a water potential gradient between STEs and surrounding cells)
        
        Water enters sieve tube from xylem due to water potential differential, creating turgor pressure
        
        Photosynthate moves by bulk flow to nearest/strongest sink and is unloaded (Sucrose actively transported from sieve tube)
        
        Water moves from root to atmosphere in a single direction
        
        Assimilate moves from source to closest sink