BFI Midterm Plants

• The light dependent Reaction

  Thylakoid, PSII, PSI, CC, ATP synthase complex, e-, NADPH, ETC, CC Cytochrome complex, ETC Electron Transport chain, PS photosystem I, PSII photosystem II, Thylakoid Lumen, Thylakoid membrane, Stroma
• Xylem

  • Water transport, structural support
• Steps in the correct order for transpiration

  • Water evaporates from the leaves, forces of cohesion and adhesion cause water molecules to form a column in the xylem, water is passively transported into the roots and then into the xylem by osmosis
• Translocation of Sucrose

  Sugar loading into the phloem, water flow into the phloem by osmosis, downward movement of sap from high pressure to low pressure cell, unloading sucrose from the phloem into the sink, water moves back into xylem by osmosis, then moves up by transpiration
• Plant tissues

  • Dermal
  • Ground
  • Vascular
• Transpiration of water

  Water evaporates from the leaves, forces of cohesion and adhesion cause water molecules to form a column in the xylem, water is passively transported into the roots and then into the xylem by osmosis
• Stem adaptations

  • Stolons
  • Rhizome
  • Tubers
• Phloem components

  • Sieve tubes
  • Phloem fibers
  • Companion cells
  • Phloem Parenchyma
• Plant nutrition

  Often involves relationships with other organisms
• Mutualistic Bacteria

  • Rhizobacteria
  • Endophytes
• Rhizobacteria

  • Thrive in the rhizosphere
  • The layer of soil surrounding the plant's roots is the rhizosphere
  • Non-pathogenic bacteria

  
• Endophytes

  • Live between the cells of host plant tissues
• Bacteria need 8 ATP to convert one molecule of N2 to NH4+
• Nitrogen-Fixing Bacteria

  • Nodules, composed of plant cells "infected" by nitrogen-fixing Rhizobium
  • Inside the root nodule, Rhizobium bacteria called bacteroids
• The plant obtains fixed nitrogen from Rhizobium

  Rhizobium obtains sugar
• The chemical dialogue between Rhizobium bacteria and root cells of their specific plant hosts

  
• Nitrogen Fixation and Agriculture

  • Crop rotation

  
• Early land plants would have encountered harsh conditions 400 to 500 million years ago
• Non-mutualistic plants

  • Epiphytes
  • Parasitic plants
  • Carnivorous