photosynthesis

• What is the process by which plants make their own food?

  Photosynthesis
• What do plants use to make glucose during photosynthesis?

  Energy from the sun or an artificial source
• What is biomass in the context of photosynthesis?

  The mass of living material in an organism
• How does energy stored in biomass relate to the food chain?

  It supports nearly all life on Earth as animals eat plants and each other
• Where does photosynthesis occur in plants?

  Inside chloroplasts
• What role does chlorophyll play in photosynthesis?

  It absorbs light energy
• What is the equation for photosynthesis?

  6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂
• What type of reaction is photosynthesis?

  It is an endothermic reaction
• What happens during the first stage of photosynthesis?

  Energy from light is used to split water into oxygen gas and hydrogen ions
• What occurs in the second stage of photosynthesis?

  Carbon dioxide combines with hydrogen ions to make glucose
• What factors affect the rate of photosynthesis?

  Light intensity, concentration of CO₂, and temperature
• What does it mean when a factor is described as a limiting factor in photosynthesis?

  It stops photosynthesis from happening any faster
• How can you investigate the effect of light intensity on the rate of photosynthesis?

  By moving the lamp closer to or further away from the plant
• What does the rate of oxygen production indicate in the context of photosynthesis?

  It corresponds to the rate at which photosynthesis is occurring
• What is the basic method for measuring the rate of photosynthesis using pondweed?

  Measure the length of the gas bubble produced in a capillary tube
• Why should other variables be kept the same during the experiment?

  To ensure that only the factor being investigated affects the results
• What happens to the rate of photosynthesis as light intensity increases?

  It increases steadily up to a certain point
• What occurs when light intensity or CO₂ level becomes the limiting factor?

  The rate of photosynthesis does not increase further
• How is light intensity related to distance from the light source?

  Light intensity decreases in proportion to the square of the distance
• What is the inverse square law in relation to light intensity?

  Light intensity (I) α 1/distance (d)²
• What happens to the rate of photosynthesis if there is too little carbon dioxide?

  It slows down
• What is a common method to control the concentration of CO₂ in experiments?

  Dissolve different amounts of sodium hydrogen-carbonate in the water
• Why is temperature often a limiting factor in photosynthesis?

  Because enzymes work more slowly at low temperatures
• What happens to enzymes at high temperatures during photosynthesis?

  They can become denatured, decreasing the rate of reaction
• At what temperature can enzymes start to denature in plants?

  About 45°C
• What is the best way to control the temperature of a boiling tube in an experiment?

  By placing it in a water bath
• What are the three limiting factors of photosynthesis?

  • Light intensity
  • Concentration of carbon dioxide (CO₂)
  • Temperature
• What are the stages of photosynthesis?

  1. Light energy splits water into oxygen gas and hydrogen ions.
  2. Carbon dioxide combines with hydrogen ions to form glucose.
• How do light intensity, carbon dioxide concentration, and temperature interact as limiting factors in photosynthesis?

  • Light intensity increases photosynthesis until a limit is reached.
  • CO₂ concentration increases photosynthesis until a limit is reached.
  • Temperature affects enzyme activity, influencing the rate of photosynthesis.