leaves

• leaves use a process called photosynthesis to make their food
• chloroplasts are found inside cells, they contain chlorophyll which gives plants their green colour
• photosynthesis is the production of glucose from carbon dioxide using sunlight as an energy source.
• the main function of the leaf is photosynthesis
• the stomata is the opening on the underside of the leaf that allows gases to enter or leave the plant
• stomata open during daylight hours when it's warm and close at night time when its cold
• carbon dioxide enters through stomata on the underside of the leaf
• a vein is a long narrow tube that carries water or sap through the plant
• water moves into the root hair cell by osmosis
• a waxy cuticle covers the surface of the leaf to prevent too much water loss by evaporation
• if there isn't enough co2 then the rate of photosynthesis will be slow
• if there isn't enough co2 then the rate of photosynthesis will be slow
• leaves use a process called photosynthesis to make their food
• photosynthesis involves:

  1. carbon dioxide
  2. water(from the moisture from soil)
  3. sunlight
  4. chlorophyll(found in chloroplast)
• adaptations of a leaf

  1. large surface area
  2. thin and flat
  3. the spongy mesophyll is spread out
  4. the palisade mesophyll is spread out
  5. has a xylem and phloem
  6. has a waxy cuticle
  7. has guard cells
• the palisade mesophyll has lot of chloroplast to maximise energy output
• the spongy mesophyll allows gas exchange between air spaces and atmosphere
• guard cells control opening and closing of stomata
• xylem transports water upwards through plant
• phloem transports carbohydrates through plant
• to test for starch in a leave you need to:

  • boil the leaf in water
  • boil the leaf in ethanol
  • rinse the leaf in water
  • put the leaf on a white tile and drop a few drops of iodine
  • the leaf should turn blue black if it has iodine
• what is a variegated leaf?


  it is a leave with different colours
• what. part of a variegated leaf will turn blue black during the test for starch?

  the green part
• factors that affect photosynthesis are:

  1. light intensity
  2. co2 concentration
  3. temperature
• magnesium is. used in making the plants chlorophyll without
• magnesium is used in making chlorophyll for the plant without is the plants leaves will turn yellow
• nitrate used in making amino acids without it the plant would have a stunned growth
• the roots functions

  • absorbs water, minerals and salts
  • the anchor the plant firmly to the soil providing support
  • some roots can store food
• the root hair cells functions/adaptations:

  • they are numerous and long(to provide a large surface area)
  • they have lots of mitochondria
  • have thine cells walls so minerals can easily pass through
  • they have a large cell vacuole