leaf structure

• Guard Cells - specialized cells surrounding stomata that control its opening and closing
• Palisade cells - contain lots of chloroplasts and are found in the upper part of the leaf
• Guard cells regulate gas exchange between the atmosphere and the internal tissues of plants through stomatal pores.
• Cuticle is a waterproofing layer made up of waxes and lipids to prevent excessive transpiration.
• Stomata - opens up so that carbon dioxide can diffuse into the leaf.
• Epidermis - outermost layer of plant tissue, protects against pathogens and prevents excess water loss.
• Vascular bundle - contains a hollow tube specifically for water movement called the xylem.
• Phloem - transports of sugar
• Xylem - transports of water
• Spongy mesophyll - loosely arranged cells with air spaces between them
• Palisade mesophyll - tightly packed cells containing chloroplasts
• Guard cell - controls opening/closing of stomata
• Transpiration - evaporation of water from plants through their stomata
• Iodine test

  • boiling water - will break open the leaf's cell wall and cell membrane.
  • ethanol - will remove the chlorophyll out from the plant cell (decolourise)
  • water - wash off excess ethanol.
  • iodine - turns blue black in the presence of starch.
• Starch is stored in sap vacuole in the leaf.
• Magnesium - is needed to make chlorophyll, the leaves will look yellow if there's not enough magnesium.
• Nitrate - is needed for plants to change carbohydrates to protein, if not they can't grow well.