Photosynthesis (OCR GCSE Combined Science A (Gateway): Biology)

Exam Questions

34 mins12 questions
1
Sme Calculator
1 mark

An experiment is set up with four test tubes as shown in the diagram below. All four test tubes are left in sunlight for 6 hours.

1-2

Which test tube would contain the least amount of dissolved carbon dioxide after 6 hours?

    Did this page help you?

    2
    Sme Calculator
    1 mark

    Which statement correctly describes why plants are called primary producers?

    • They release oxygen into the atmosphere

    • They use chemical energy from the sun to produce glucose

    • They release heat energy during photosynthesis

    • Energy stored in the biomass of plants makes its way through the food chain

    Did this page help you?

    3
    Sme Calculator
    1 mark

    The process of photosynthesis happens in two main stages.

    Which row accurately describes each stage?

     

    Stage 1

    Stage 2

    A

    Energy from light splits water into oxygen gas and hydrogen ions

    Carbon dioxide combines with hydrogen ions to make glucose

    B

    Carbon dioxide combines with water

    Glucose is made and oxygen released

    C

    Carbon dioxide is taken into the leaf through stomata

    Energy from light is used to combine carbon dioxide with hydrogen

    D

    Energy from light splits carbon dioxide into carbon and oxygen atoms

    Water combines with the carbon and oxygen atoms to make glucose

      Did this page help you?

      4
      Sme Calculator
      1 mark

      The following experimental set-up is used to measure the rate of oxygen production of an aquatic plant from photosynthesis.

      The experiment was repeated several times and the mean volume of oxygen collected was determined. 

      insert-diagram_-6-q9-experiment

      Which two factors should be kept constant during the experiment?

      • The size of the funnel and temperature of the water.

      • The size of the aquatic plant and the amount of water in the beaker.

      • The size of the aquatic plant and the amount of gas in the measuring cylinder.

      • The distance from the light source and size of the aquatic plant.

      Did this page help you?

      5
      Sme Calculator
      1 mark

      The diagram below shows the results of three experiments to measure the rate of photosynthesis under different conditions.

      Experiment 1 measured the effect of light intensity on photosynthesis

      Experiment 2 measured the effect of temperature on photosynthesis

      Experiment 3 measured the effect of carbon dioxide on photosynthesis

      6-q5-limiting-factors

      Which of the following correctly identifies the limiting factor for photosynthesis in each experiment?

       

      1

      2

      3

      A

      light intensity

      light intensity

      carbon dioxide concentration

      B

      temperature

      temperature

      light intensity

      C

      light intensity

      temperature

      carbon dioxide concentration

      D

      light intensity

      carbon dioxide concentration

      temperature

        Did this page help you?

        6
        Sme Calculator
        1 mark

        Higher Tier Only

        The graph shows the effect of carbon dioxide concentration on the rate of photosynthesis.

        q5-paper1h-spec2018-ocrgcsebio

        Where on the graph is carbon dioxide a limiting factor?

        • X only

        • X and Y

        • Y and Z

        • Z only

        Did this page help you?

        7
        Sme Calculator
        1 mark

        Higher Tier Only

        The inverse square law in relation to light intensity (i) and distance (d) from the light source is shown by:

        • i ∝ d2

        • i ∝ 1/d2

        • i2 ∝ 1/d

        • i2 ∝ d

        Did this page help you?

        8
        Sme Calculator
        1 mark

        Higher Tier only

        A light source is placed 0.5m from a plant. The relative light intensity falling on the plant is 2 units.

        The light source is moved to 1m away.

        What is the relative light intensity falling on the plant now?

        • 0.125

        • 0.25

        • 0.5

        • 1.0

        Did this page help you?