6.1 photosynthesis

Cards (22)

  • balanced chemical equation:
    6CO2 + 6H2O -> C6H12O6 + 6O2
  • plant cells take in oxygen & release carbon dioxide as a result of aerobic respiration
  • plants photosynthesize and respire during the day
  • plants only respire at night
  • rate of photosynthesis is higher than respiration during the day
  • daytime
    net diffusion of CO2 into plant & O2 out of plant is high
  • nighttime
    net diffusion of CO2 out of plant & O2 into plant is high
  • when there's low light intensity during the day, rate of photosynthesis and respiration is equal. therefore, there is no net movement of O2 or CO2 in either direction
  • yellow colour indicates high carbon dioxide level (respiration)
  • red colour indicates carbon dioxide level is equal to atmosphere
  • purple colour indicates low carbon dioxide level (photosynthesis)
  • glucose is too soluble to be transported around plant alone. therefore, it is converted to more complex carbohydrates
  • glucose can be converted to starch to store energy
  • glucose can be converted to cellulose, which can be used to build cell walls
  • glucose can convert to sucrose so it can be transported around the plant, in the phloem
  • glucose can be used as nectar to attract insects for pollination
  • glucose is used in respiration to provide energy
  • two important mineral requirements:
    • nitrate ions - to make amino acids
    • magnesium ions - to make chlorophyll
  • nitrate ion deficiency would:
    • slow down growth of plant
    • cause the leaves to turn yellow
  • a magnesium ion deficiency would:
    • cause leaves to turn yellow between their veins, starting from the lower leaves
    • slow down growth of plant
  • factors needed for photosynthesis to take place:
    • chlorophyll - helps absorb the light required
    • light - provides energy to drive the reaction
    • carbon dioxide - converted into sugars such as glucose
  • factors affecting the rate of photosynthesis:
    light intensity, carbon dioxide concentration, temperature