plants

• hypertonic


  higher con. of solutes outside the cell than inside the cell (water moves out)
• isotonic


  equal conc. of solutes inside and outside the cell (water moves EQUALLY in and out)
• hypotonic


  higher conc. of solution inside the cell than outside the cell (water moves in)
• Root below ground


  primary - anchors the plant to the soil. absorbs nutrients and water (thick)

  secondary - increases the SA:V ratio to maximise the absorption(thin)
• Vascular system


  Xylem - transports water (1 direction up)

  Phloem - transports nutrients and sugar (both direction)

  *xylem and phloem are the types of vascular tissue in plants*
• Root System


  absorption occurs via two different pathways:

  Extracellular pathway - water diffuses into the roots in the gaps

  between cells and enter cells when they encounter a Casparian strip

  Cytoplasmic pathway - passive diffusion or active transport of water into root cells
• Xylem


  -Long, skinny and continuous tube made from two cell types: vessel elements and tracheids

  • Both are hollowed cells, lignified (dead) and pits (perforations)
  • Vessel element is much larger and they joining end to end
  • tracheids are tapered end to end (points triangle end)
• Phloem 


  -transports nutrients/food from the leaves to the cells

  -Sieve cells are non-lignified, hollow cells separated by sieve plates with perforation between cells (think like filter)

  -Companion cells are next to sieve cells to regulate nutrient entry and keep sieve cells alive
• Transpiration


  Cohesion - water molecules are polar so they attract each other and will pull water molecules up the xylem

  Adhesion - water molecules are attracted to the walls of the xylem, so will slowly travel up xylem (capillary action)