Nutrition in plants

• How does photosynthesis happen?

  The chlorophyll in the plant absorbs sunlight and uses its energy to convert carbon dioxide and water into glucose and oxygen is also produced
• Why is photosynthesis an important process?

  It converts light energy to chemical energy, which is stored in the glucose.
• What's the word equation for photosynthesis?


  Carbon dioxide + water -> (light and chlorophyll) Glucose + oxygen
• What's the balanced symbol equation for photosynthesis?

  6CO2 + 6H20 ->(light + chlorophyll) C6H12O6 + 6O2
• How does light intensity affect the rate of photosynthesis?


  Increasing light intensity increases the rate of photosynthesis only up to a certain point
• How does carbon dioxide concentration affect the rate of photosynthesis?

  Increasing the carbon dioxide concentration increases the rate of photosynthesis and too little carbon dioxide slows it down
• How does temperature affect the rate of photosynthesis?

  Increasing the temperature increases the rate of photosynthesis, however if the temperature is too high the plants enzymes can denature
• How is the surface area of a leaf adapted for photosynthesis?


  The leaves are broad, so there's a large surface area exposed to light
• Where are the chloroplasts found in the leaves for efficient photosynthesis?

  The chloroplasts are found in the palisade layer, so they're near the top of the leaf where they can get the most light
• How is the upper epidermis adapted for photosynthesis?

  it is transparent to allow sunlight through to the palisade layer
• How are the vascular bundles adapted for photosynthesis?

  They deliver water and other nutrients to every part of the leaf and takeaway the glucose produced by photosynthesis. They also help to support the leaf structure
• How is the waxy cuticle adapted for photosynthesis?

  It helps to reduce water loss by evaporation
• Why do plants need mineral ions?

  They're required for growth and without them plants get deficiency symptoms
• What do nitrates do for plants?

  Makes amino acids and proteins Needed for cell growth If a plant can't get enough nitrates it will be stunted and older leaves will turn yellow
• What do phosphates do for plants?

  Makes DNA and cell membranes They're needed for respiration and growth Plants without phosphate have poor root growth and their older leaves are purple
• What does potassium do for plants?


  Helps enzymes needed for photosynthesis and respiration If there's not enough potassium plants have poor flower and fruit growth and discoloured leaves
• What does magnesium do for plants?

  Magnesium is required for making chlorophyll Plants without enough magnesium have yellow leaves
• Practical: Investigation photosynthesis

  Take a boiling tube and place it 10 cm away from a led light source Put sodium hydrogen carbonate solution in the boiling tube because it releases carbon dioxide as well as a piece of pondweed Leave it for 10 minutes Count the number of bubbles produced in one minute and repeat this two times and find the mean Repeat this at a distance of 20,30, and 40 cm away A problem with this experiment could be that the bubbles may be too fast too count and the bubbles are not always the same size To fix this we can measure the volume of oxygen produced instead