Gen Bio

• Shoot system


  Above ground (stems and leaves)
• Root system


  Underground (roots)
• Xylem transports water and minerals in UPWARD directions
• Xylem


  • Consists of tracheary elements: Tracheids (narrower, have pits at ends that allow water transport) and Vessel Elements (wide thin walled. To transport and support)
• Root pressure

  1. Water is still collected by the ROOTS

  2. Water flows in creating pressure

  3. This UPWARD PUSH of xylem is called ROOT PRESSURE
• Guttation


  Exudes water from leaf margins instead in stomata
• Capillary action


  Tendency of liquid to move up against gravity when capillary or small tube is enclosed
• Capillary action


  • Surface Tension - Hydrogen Molecules
  • Adhesion - Unlike Molecules
  • Cohesion - Like Molecules
• Phloem


  Transports sugar or other components
• Phloem

  • Composed of: Sieve Pore, Companion Cell (this does not participate in transporting of sugar.), Phloem Parenchyma, and Sieve-Tube Elements
• Phloem sap


  Food transported from a sugar source (where sugar is being produced, usually leaves) to a sugar sink (it consumes and stores sugar, usually roots, growing stems, buds, and fruits)
• Sugar sinks and sources


  Can change depending on the seasons and stages of development
• Pressure


  Created at the source while producing sugar, then decreases at the sink as it is used
• Translocation


  Moves the sugar in the phloem to the parts that need it
• End of dormancy period


  The plant withers due to the onset of a new season
• Growing period


  Parts of plants that were sugar sinks become the sugar sources
• Pressure flow model


  1. Potential results in movement from xylem to phloem

  2. This movement creates high pressure potential called "high turgor pressure" within the phloem

  3. High turgor pressure moves phloem sap from source to sink by "bulk flow"

  4. Bulk flow helps sugars be rapidly removed from the sink, increasing the solute potential, forcing the water to move from phloem back to the xylem, leading to a lower solute potential
• Vascular bundle (dicot)


  Ring-like structure
• Vascular bundle (monocot)


  Scattered structure
• Elements for growing plants

  • Macronutrients from air and water: Carbon, Hydrogen, Oxygen
  • Macronutrients from soil: Nitrogen, Phosphorous, Potassium, Calcium, Magnesium
  • Micronutrients in Soil: Boron, Chlorine, Copper, Iron, Manganese, Molybdenum, Nitrogen, Zinc
• Asexual reproduction


  Produces individuals that are GENETICALLY IDENTICAL to the parent plant
• Vegetative propagation


  A process in which new plants are grown from the old parts of another plant like roots, stems, shoots, and leaves, without reproductive organs involved
• Apomixis


  An asexual mode of reproduction through seeds
• Sexual reproduction


  Results from fertilization, the union of gametes from two GENETICALLY DIFFERENT plants
• Pollination (angiosperms)


  The process by which pollen is taken from "anthers" (part of male organs, where pollen is made) to the "stigma" (female part of the flower)
• Gymnosperms


  Leafy green sporophyte generated cones containing male and female gametophytes
• Sexual spores


  Plants produce hundreds of spores and the spore sac bursts (sporangia)
• Phytohormones


  Chemicals produced by plants that regulate their growth, development, reproductive processes, longevity, and even death
• Plant Tissue Culture


  The use of small pieces of plant tissue (explants) which are cultured in a nutrient medium under sterile conditions
• GMO (Genetically Modified Organism)


  A technology that involves inserting DNA into the genome of an organism