Factors Affecting photosynthesis

Cards (13)

  • As the light level is raised, the rate of photosynthesis increases but only up to a certain point
  • You can investigate light intensity by moving a lamp closer or further away from your plant
  • The distance from the lamp and light intensity are inversely proportional to each other, meaning as the distance increases, light intensity decreases
  • Plants need to carry out photosynthesis to survive, which is dependent on four main factors: light intensity, temperature, the concentration of carbon dioxide in the air, and the amount of chlorophyll that the plants have.
  • Chlorophyll is the pigment within chloroplasts that absorbs the light energy needed for photosynthesis, and its level within an individual plant can vary due to disease, environmental stress, or lack of nutrients.
  • When we talk about limiting factors for photosynthesis, we're normally referring to light, carbon dioxide, and temperature.
  • As light intensity increases, the rate of photosynthesis also increases, but after a certain point, the rate plateaus because when light is plentiful, something else becomes the limiting factor.
  • Temperature affects the rate of photosynthesis, with the rate rising initially because the enzymes involved can work more quickly and the molecules can move faster, but after a while, the rate starts to drop again as the enzymes involved begin to denature.
  • More than one limiting factor can be represented within a single graph
  • Farmers often use greenhouses to create conditions for high rate of photosynthesis, trapping the sun's heat and providing artificial light so that photosynthesis can continue all through the day and night.
  • The role of chlorophyll is to absorb light energy for photosynthesis
  • Plants might not produce enough chlorophyll because:
    • They have a disease like tobacco mosaic virus
    • They lack the required nutrients
  • Role of carbon dioxide in photosynthesis:
    1. During photosynthesis, carbon dioxide is taken in by the plant through small pores on the leaf surface called stomata.
    2. Inside the leaf, carbon dioxide combines with water that is absorbed by the plant's roots.
    3. Through the process of photosynthesis, these reactants are used to produce glucose and oxygen.
    4. The glucose serves as a source of energy and a building block for the plant, while oxygen is released as a byproduct.