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

Photosynthesis. In practice, TEMPERATURE, CARBONDIOXIDE, and LIGHT INTENSITY can interact to the limit of the rate of photosynthesis

Extracts from this document...


Kieron Fenn Biology coursework Photosynthesis. Green plants don't absorb from the soil. They make their own food, using sunlight. This is called photosynthesis, which actually means 'making through light'. It occurs in the cells of green plants, which are exposed, to light. Carbon + Water LIGHT Glucose + Oxygen Dioxide CHLOROPHYLL 6Co2 + H2O C6H12O2 + 6O2 Some of the glucose produced in photosynthesis is used immediately by the plant to provide energy via respiration. However, much of the glucose is converted into insoluble starch for storage in the stem, leaves or roots. In practice, TEMPERATURE, CARBONDIOXIDE, and LIGHT INTENSITY can interact to the limit of the rate of photosynthesis. Anyone of them in particular at a particular time may be the limiting factor. With photosynthesis the more intense the light or the more amount of light the plants get, the more photosynthesising the plant will do. This means that I will be able to predict that my graphs up to a certain extent will be directly proportional. This also means that the light intensity will always limit the light of photosynthesis. There will be a point in the graph where the light will not effect the rate of photosynthesis. Therefore there must be some other limitation effecting the rate of photosynthesis which will either be the dark reaction, the carbon dioxide or the temperature. ...read more.


Method Fill the boiling tube with water and add 1g to the sodium hydrogen carbonate. Then place the Canadian pond weed using the tweezers. Then place the boiling tube in the water bath and take the temperature. Then place the water bath in front of the light source and wait for the bubbling to star. If there is no bubbling then you must snip a piece off the top of the weed. Place the light source at your chosen distances and count the bubbles for 1 minute each time. The conditions that we had to use were the room had to be dark and the temperature of the solution was 19 degrees Celsius. Diagram Analysis The graphs I have laid out are concave curves, which is what you would have to expect from graphs with direct proportion. The plots show and the lines show the results, on the distance/bubbles graph, you will be able to see that I have plotted an average as well as the previous three attempts. On the second graph you can see that I did no plot and show the previous three attempts because I felt that it was not necessary. The curves on both of the graph show that the rate of photosynthesis never reached zero as I predicted in the hypothesis, this is because the room never was totally dark. ...read more.


Although I think that the reliability of the experiment was not as good as it could be, I think that the experiment was not really that effected, and it wasn't that much of a problem. To make my results reliable and good I decided to do them three times and then take an average to produce the graph and from the graph I would say that my results were suitable and very reliable. My results produced similar graphs to what I had hypothesised in my hypothesis. I feel that the distance graph was inversely proportional like I said in my theory and the intensity graph was directly proportional. I did not get very accurate answers because some of the bubbles were bigger than the others. To make more accurate results I would use a more accurate method as shown below. As you can see the bubbles produced by the plant is automatically drawn up the capillary tube and then they congregated at the corner. After one minute I will pull back the syringe and this will draw one big bubble to the end of the syringe. Then I will be able to measure the bubble with a ruler. After knowing this information and the circumference of the capillary tube you can then work out the surface are therefore giving a more accurate result. By Kieron Fenn. ...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

    Light Intensity and Photosynthesis.

    4 star(s)

    Bubbles (cms) (lux) 45 55 12 40 80 12 35 110 13 30 149 14 25 208 16 20 310 18 15 590 20 10 945 21 5 1015 21 Although this is a very quick, simple and efficient way of obtaining an idea of the trends for the graph,

  2. Experiment to Investigate the Effect of Temperature on the Rate of Photosynthesis in Elodea.

    The percentage error of the syringes used for the small volumes taken was extremely small, so syringes were more practical to use in this experiment. One of the largest sources of error in this experiment was temperature control. It is extremely to keep the temperature constant for three readings using just ice and hot water.

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

    The light-independent reactions of photosynthesis These series of reactions occur in the stroma. The fixation of carbon dioxide is a light-independent process in which carbon dioxide combines with a five-carbon sugar, ribulose bisphosphate (RuBP), to give two molecules of a three-carbon compound, glycerate 3-phosphate (GP).

  2. How does light intensity affect the rate of photosynthesis

    plant at the start and therefore using the photosynthesis equation in my prediction I can say that all of the compounds on the other side of the equation were made by the plant and that one of these is oxygen and therefore the bubbles of gas that I saw in the water must have been oxygen.

  1. Mangrove Soil Analysis

    Whilst the agar is warming take the 6 small beakers and label them. 3. Add 1 teaspoon of dirt to the appropriately named beaker and add 50mL of water to each beaker. 4. Thoroughly mix the dirt in the beaker until as much of it has dissolved as possible.

  2. To investigate how light intensity affects the rate of photosynthesis of pond weed at ...

    - I could have improved my investigation by making sure that there was a constant stream of bubbles being produced by the plant and by making sure that most of the bubbles were roughly the same size. However, this is impossible to do so it will always be a problem in analysing whether my results are accurate or not.

  1. How temperature affects the rate of photosynthesis.

    rate at which photolysis takes place. This is because the action of enzymes depends on the temperature as a low temperature would reduce there action (low kinetic energy) whereas a high temperature of about 40 degrees would increase the rate at which they carry out their processes (high kinetic energy).

  2. What is the effect on the rate of respiration of yeast cells with glucose ...

    Pour this into a 250ml beaker to allow enough space for the activation of yeast and glucose. Leave it for 5 minutes. * Measure out 20ml and pour it into the conical flask * Immerse the conical flask in the water bath for 5minutes and set the timer for 2

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