• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

An investigation into the effect of light intensity on the rate of photosynthesis on Canadian pondweed.

Extracts from this document...


An Investigation into the Effect of Light Intensity on the Rate of Photosynthesis on Canadian Pondweed Background Information: Photosynthesis is an organic chemical reaction which green plants use to produce glucose from carbon dioxide and water. Its equation is 6CO[2] + 6H[2]0 C[6]H[12]O[6] + 6O[2] However, carbon dioxide and water cannot react on their own "They have to be given energy to make them combine. The energy which green plants use for this is sunlight energy". We can determine that if sunlight gives the reaction energy, and increase in the intensity of the sunlight will give the reaction more energy, which will speed the reaction up. We can therefore safely predict that as the intensity of the light increases, so too will the speed of the reaction. List of Key Variables: The key variables that could affect my experiment are the temperature at which the water is, a thermometer will be used and if the temperature rises or falls we will need to restart because this could affect the whole experiment. ...read more.


Prediction and Hypothesis: In this experiment we will be investigating whether or not the light intensity will change the rate of photosynthesis in Canadian pondweed. We will be doing this by seeing the rate at which oxygen bubbles are produced, because when photosynthesizing the Canadian pondweed produces bubbles and we can see the rate of bubbles against light intensity. The further the light away from the pondweed the less the light intensity, so the less the amount of bubbles produced, as shown in the graph below. I think if I double the distance the light is away from the pondweed. Then the rate at which the bubbles are produced will half because they are directly proportional to each other because the pondweed produces the bubbles when it is photosynthesizing it produces oxygen bubbles so the light = bubbles so the less the amount of light the less the amount of bubbles. BUBBLE RATE LAMP DISTANCE AWAY FROM PONDWEED [image003.gif] BUBBLE RATE [image005.gif] LIGHT INTENSITY Observations: We will be observing how many bubbles are produced against the light intensity then recording the results onto a table. ...read more.


Set up apparatus as above. 2) Fill the test-tube with pond water, and then in the large beaker of cold water. 3) Insert a thermometer into the beaker, and record the temperature at the beginning and end of each experiment, merely as a precaution against a significant rise in temperature, which is not expected. 4) Set up a lamp at a set distance from the plant, ensuring that this distance is from the filament of the lamp to the actual pondweed, rather than the edge of the beaker. 5) The light intensity was measured in the same way as described in the preliminary experiment, and assumed to be the same at any point at any particular distance. 6) When bubbles are being produced at a steady rate, clear any previous bubbles from the tubing by moving the syringe. 7) Start the stopwatch, and wait for 1 minute. 8) Move the bubbles, which have been collected at the bend in the tubing to the part of the tube with a scale. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Green Plants as Organisms section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Green Plants as Organisms essays

  1. Marked by a teacher

    An investigation into the effect of light intensity on the rate of photosynthesis of ...

    5 star(s)

    If I use a land plant, I will not be able to tell how much oxygen has been produced. So I will not be able to find out the rate of photosynthesis. Also if I use a land plant, water will likely to be a limiting factor as if the soil is not wet enough.

  2. Marked by a teacher

    An investigation into the effect of a germination inhibitor on the germination of seeds.

    3 star(s)

    chi-squared for group data is different than the individual data because there is more than one set of results. Since there is 6 sets to be dealt with, then a mean result for each concentration is used (i.e. for 0% concentration for day 6 then add up all 6 results

  1. The effect of light intensity on the rate of photosynthesis

    The green pigment chlorophyll is held in small disc-like shapes, made from specialized parts of the cytoplasm, called chloroplasts. The central part of the cell is a vacuole containing cell sap, which is mainly water. The cytoplasm is surrounded by a cell- surface membrane. A nuclear envelope surrounds the nucleus.

  2. Investigating the effect of temperature on the rate of photosynthesis

    Hold test tube up with stand and clamp, and hold elodea upside down by putting it inside the tubing. Pull through any bubbles before starting the experiment. This is done so that no excess bubbles are already there, which will make the experiment inaccurate.

  1. An experiment to investigate the effect of Light intensity on the rate of photosynthesis.

    The best-fit line shows the correlation between the two as it lies along the line created by most of the points. This shows there to be a direct correlation between the results. As there is a direct correlation, the gradient of the graph at each of the different points should be around the same amount.

  2. Investigate the effect of light intensity on the rate of photosynthesis in an aquatic ...

    I also decided I would take the results of the outcome variable within a 5 minute time limit, and for this aspect of the investigation, I would not take repeat results. I also decided though, that I would count the number of bubbles, and that if there were a large

  1. An Investigation into Species Diversity with distance along a Pingo.

    Succession can be seen across the pingo, where the vegetation changes from grasses and herbs to shrub and finally trees and woodland. As succession occurs the number and type of species change, as does the complexity of species and vegetation height.

  2. How temperature affects the rate of photosynthesis.

    The volume of oxygen released will be the highest at 35 oC and lowest at 0 oC. The optimum temperature i.e. the temperature at which the rate of photosynthesis is the highest is predicted between 35-45 oC. So the largest air bubble would be measured between these temperatures.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work