Biology~plant tissue

• Plant tissues


  • Plant cells, tissues and organs are adapted to their functions
  • The stem, root and leaves form an organ system that transports substances into, around and out of a plant
• Enzymes


  • They increase the rate of chemical reactions without themselves being consumed or permanently altered by the reaction
  • They increase reaction rates without altering the chemical equilibrium between reactants and products
• As temperature increases


  The rate of reaction increases
• Plant transport tissues


  Xylem and phloem
• Need for transport in plants


  To transport substances into, around and out of the plant
• Transpiration


  The loss of water from leaves by evaporation through the stomata
• Factors affect transpiration
• Investigating transpiration
• Measuring water uptake - potometers
• Environmental factors on water using potometers
• Investigate distribution of stomata and guard cell
• Plant tissues - epidermis, palisade mesophyll and spongy mesophyll

  • The structure of the tissues is related to their functions in the plant
• Palisade mesophyll


  Plant tissue containing closely packed cells in the upper layer of a leaf, adapted to absorb light efficiently
• Spongy mesophyll


  The plant tissue in a leaf which has loosely packed cells and air spaces between them to allow gas exchange
• Chloroplast


  Contains the green pigment chlorophyll; the site of photosynthesis
• Photosynthesis


  A chemical process used by plants to make glucose and oxygen from carbon dioxide and water, using light energy. Oxygen is produced as a by-product of photosynthesis. Algae subsumed within plants and some bacteria are also photosynthetic.
• Plant leaves are adapted for photosynthesis and the exchange of gases required for the process