4.4.1.2 rate of photosynthesis

• What are the limiting factors of photosynthesis?

  • Light intensity
  • Carbon dioxide concentration
  • Temperature
• what is a limiting factor?

  A factor that restricts the growth or distribution of a population in an ecosystem.
• what environmental conditions limit photosynthesis at a particular time?

  • At night: light is a limiting factor
  • In winter: temperature is a limiting factor
  • If its warm and bright: carbon dioxide is a limiting factor
• how does the rate of photosynthesis increase as the light level is raised?

  increases steadily but only up to a certain point
• when will the amount of carbon dioxide increase until?

  a certain point - afterwards the graph flattens out
• why does temperature affects photosynthesis?

  enzymes are involved
• when is temperature normally a limiting factor?

  when the temperature is too low so the enzymes work more slowly
• what happens if the plat gets too hot?

  the enzymes will denature
• what are distance and light intensity?

  directly proportional to each other
• what is the inverse square law?

  $\frac{1}{d^2}$
• what does the inverse square law mean?

  light intensity decreases with the square of the distance.
• what is the most common way of creating the ideal environment for plants?

  in a greenhouse
• what do greenhouses do?

  help trap the Sun’s heat and make sure the temperature doesn’t become limiting