Photosynthesis

• Photosynthesis


  Water + Carbon dioxide -> Glucose + Oxygen
• Chemosynthesis


  Using chemical reactions to make food (glucose)
• Uses of glucose


  • Make new cells
  • Make cellulose
  • Make starch
  • Make fat
• Plant cell


  • Cell wall
  • Chloroplasts
  • Mitochondria
  • Vacuole
• Animal cell


  • Cell membrane
  • Nucleus
  • Cytoplasm
  • Mitochondria
• Organelle functions


  • Nucleus - Contains DNA, controls cell
  • Cytoplasm - Where chemical reactions happen
  • Cell membrane - Controls what enters the cell
  • Mitochondria - Carries out respiration
  • Cell wall - Gives the cell structure (plant cells only)
  • Chloroplasts - Carry out photosynthesis (plant cells only)
  • Vacuole - Stores water (plant cells only)
• Transport in plants


  1. Phloem - Transports organic molecules, water and food

  2. Xylem - Transports water and minerals up from the roots to the leaves
• Translocation


  The movement of sugars up and down the phloem from sources to sinks
• Transpiration


  The movement of water up the xylem from the roots to the leaves
• Leaf structures


  • Upper epidermis
  • Palisade cells
  • Spongy mesophyll cells
  • Stomata pore
  • Guard cells
  • Waxy cuticle
• Palisade cells


  • Absorb light due to large number of chloroplasts
• Spongy mesophyll cells


  • Contain fewer chloroplasts than palisade cells
• Epidermis


  • Transparent cells to allow light to enter the leaf
• Waxy cuticle


  • Top layer to minimise water loss
• Guard cells


  • Open and close stomata