• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10

What affects the rate of photosynthesis in Elodea?

Extracts from this document...

Introduction

Biology Coursework What affects the rate of photosynthesis in Elodea? Aim: To find out which factors affect the rate of photosynthesis in Elodea. Variables: The variables that might affect the rate of photosynthesis in this experiment are: Temperature: When the temperature rises so does the rate of photosynthesis; this is because as the temperature around the plant rises the enzymes controlling photosynthesis inside the chloroplasts heat up and start moving around faster, the fast moving molecules collide with other fast moving enzymes causing them to react. The rate of diffusion of carbon dioxide into the leaves will also ride as temperature does. This happens because fast moving carbon dioxide molecules will hit the surface of the leaf far more often than in a colder atmosphere therefore more molecules will be taken into the leaf and diffusion will happen faster. However, the rate of photosynthesis will only keep on rising until the temperature reaches 45'c at that temperature the enzymes in the chlorophyll will be destroyed and photosynthesis will stop all together. On the other hand, if the temperature is too cold then temperature will become the limiting factor and the enzymes will stop working. Carbon dioxide: The amount of carbon dioxide in the atmosphere around the elodea affects the rate at which it will photosynthesise. The plant needs carbon dioxide to react with water molecules to make glucose. If there isn't enough carbon dioxide for the plant to take in the plant wouldn't have enough glucose or food and would die. ...read more.

Middle

The ruler needs to be straight from the boiling tube to the lamp. I will attach a paper clip firmly to the end of my elodea and place my piece of elodea into the boiling tube I will carefully cut the end of my elodea using a pair of scissors, making sure that it is kept under the water at all times. To make sure that the light intensity is entirely controlled by me I will turn off all the room lights and cut off any other major light sources. When my experiment is set up correctly I will make sure my lamp is lined up at 10 cm and turn it and the stop watch on at exactly the same time. I will then time the 2 minutes whilst counting the bubbles carefully and recording the measurements and the number of bubbles per 2 minutes. I will repeat this experiment 6 times changing nothing but the distance the light is away from the Elodea. The distances will be 10cm 20cm 30cm 40cm 50cm 60cm 70cm and 80cm. To get more accurate results I will repeat the experiment 3 times if possible Predictions: Using my scientific knowledge and the research that I have been doing I would predict that light intensity will affect the rate of photosynthesis in this way: The closer the lamp is to the elodea the stronger the light intensity will be, I know this because we have being doing tests to measure the light intensity using specialist equipment. Our findings from this are that the brighter the light or the closer the light, the stronger the light intensity. ...read more.

Conclusion

It is more likely that the similar anomalies results are due to faults the equipment that was used because we used exactly the same equipment each time. It could also be due to light coming from other sources to our experiment causing the rate of photosynthesis to rise with the light coming in though I do not know however how this could have happened in all 3 experiments. My prediction was fairly similar to the results that I got from my investigation. Conclusion Although there is a clear pattern in my experiment, as I have mentioned before, the evidence I obtained hasn't corresponded with research and other sources of information that has been found. This makes me uncertain of how accurate my results are and therefore causes me to think that the results that I have obtained are not exact enough to prove my hypothesis. The experiment was simply not carried out with enough attention to detail. This experiment could most defiantly be improved. More elodea in a larger water holder would have been better and produce many more bubbles and getting better results. The light could have been a lot brighter so, again, we would get more bubbles, and also the range of distance of which we measured could be increased. For further results, we could have tested how temperature affected the plants along with testing how carbon dioxide levels affected photosynthesis. We would achieve temperature with usage of electric heaters and thermometers and carbon dioxide by putting bottles over the plant. In summary, this whole experiment could and should have been redone, we more care, thought and better equipment. ...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. Experiment to Investigate the Effect of Temperature on the Rate of Photosynthesis in Elodea.

    of substrate molecule, as the shape of the active site will usually only allow one shape of molecule to fit in. For this reason the enzyme in said to be specific for this substrate. The enzyme then catalyses a reaction into which the substrate molecule is split into two or more molecules, called the products.

  2. Investigating the effect of Light Intensity on Elodea.

    If more energy is available, the kinetic energy is greater, so the atoms move at a greater speed. So when the particles to collide, they collide with each other with more force, therefore the activation energy is larger, making the particles more likely to react with each other.

  1. Effects of temperature and carbon dioxide on photosynthetic rate in Elodea.

    This is when photosynthesis is being carried out at a constant rate. Evaluation: A large factor in determining data accuracy is the amount of human error during experiments. The rate at which oxygen bubbles were being produced by the plant was so high that it was difficult to count the number of bubbles.

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

    The square root of the figure calculated in step 5 = 3.475145052 7. The difference between the two means (step 2) divided by the figure calculated in step 6 = 29.34384615 = 8.443919812. 3.475145052 8. 8.44 is greater than the critical value of t, which for of 24 degrees of freedom equals 2.06.

  1. How temperature affects the rate of photosynthesis.

    A high light intensity will mean more energy available for the electrons to be excited, so both cyclic and non cyclic photophosphorylation will take place at a higher rate. An increase in the rate of cyclic photophosphorylation will mean more ATP will be transported to the dark stage to be used.

  2. This experiment involves using a photosynthometer to investigate how temperature affects the rate of ...

    Ribulose Bisphosphate Carboxylase (rubisco), which catalyses the reaction between carbon dioxide and a five-carbon sugar known as Ribulose Bisphosphate (RuBp). Enzymes are catalyst made of protein. They convert substrate molecules into products by possessing an active site where the reactions occur.

  1. Investigation To Find The Effect Of Temperature On The Rate Of Photosynthesis Of Elodea.

    We measured the volume of air by pulling the syringe back and measured how much more the air bubble has increased in length using the rule on the tubing. We also learnt from the pilot study that we had to start the elodea photosynthesising straight away to make the best of time.

  2. Absorption Spectrum of Chlorophyll.

    readings from round cuvettes will give the same results for the ratio as those obtained from square cuvettes. Leaves are composed of many membranes and cell organelles. The cell wall can easily be destroyed by physically grinding the leaves, thus exposing the organelles of the plant.

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