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

Investigating the factors that will affect the rate of photosynthesis.

Extracts from this document...

Introduction

Investigating the factors that will affect the rate of photosynthesis Aim: I will be investigating how light intensity affects the rate of photosynthesis, whether it decreases or increases the rate of photosynthesis. Background Knowledge: Photosynthesis is the process by which plants make their own food. For photosynthesis to occur, plants need: * Light energy from the sun * Chlorophyll to absorb light energy * Carbon dioxide from the atmosphere and from respiration in plant cells * Water which is absorbed by the roots and transported to the leaves by the xylem tubes. Photosynthesis can be summarised by the equation: 6CO2 + 6H2O C6H12O6 + 6O2 The reactants are Carbon dioxide and Water; the products are Glucose and Oxygen. The factors that affect the rate of photosynthesis are: * Light intensity- if the light is brighter, then the rate of photosynthesis increases and visa versa. * Water supply- if a plant cannot absorb enough water, then the rate of photosynthesis decreases. * Carbon dioxide concentration- if the percentage of carbon dioxide in the atmosphere increases, so does the rate of photosynthesis. * Temperature- if the temperature increases, then the rate of photosynthesis also increases, (however, temperatures above 40OC can damage a plant and photosynthesis stops because the chlorophyll gets too hot). ...read more.

Middle

8. Boiling tube- This is where I will put the Elodea plant along with some water, so photosynthesis will take place. 9. I will use this because it is one of the reactants of photosynthesis. The measurements I will be taking are: * The amount of water in the boiling tube, in millimetres. * The distance between the Elodea and the lamp, in centimetres (10cm-60cm). * The number of oxygen bubbles produced. * The minutes of each interval for every minute, to about 5-8 minutes. Safety: 1. Do not touch the light bulb as it will be very hot. 2. Keep the lamp and boiling tube away from the edge of the table so it does not fall as smash. 3. Tie back long hair and secure loose jewellery and items of clothing. 4. Do not touch the power supply with wet hands and make sure water is not poured near the power supply. 5. When pouring water, pour it in the sink. 6. Keep eyes on experiment at all times. Method: 1. Set up apparatus as shown below. 2. Measure 10cm between the boiling tube containing the Elodea plant and the lamp. 3. Switch on the lamp and start the stop watch. 4. ...read more.

Conclusion

Evaluation: My method worked very well; there were no results which contradict my background knowledge or prediction. My step-by-step guide was very helpful and my evidence obtaining procedure work well. The quality of my result was quite high because I only had 2 anomalous results which's percentage of errors were not too great but 1 was over 10% and may be considered invalid but apart fro this most of my results are valid. My procedure was very suitable because it did not cause any mistakes which could have caused shock and unexpected results, so it is very suitable. To improve my work I could have repeated the experiment another 4 or 5 times to solidly confirm my conclusion and I could have do my experiments in a close area, where the temperature and carbon dioxide were 100% constant and therefore would not affect my results the slightest bit. Percentage of error= error/what it should be *100 = 0.3/4.2 * 100 = 7.1% This error is not over 10% and is insignificant, my result is therefore still valid. Percentage of error=error/what it should be *100 =0.25/1.25 *100 =20% This percentage is over 10% and can be considered invalid and is probably due to human error such as miscounting of the number of oxygen bubbles. ...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. Confirm which factors increases or decreases the rate of photosynthesis.

    If the photosynthesis story is sound, then the lack of any one of these three conditions should stop photosynthesis, and so stop the production of starch. In designing the experiments, it is very important to make sure that only one independent variable is altered.

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

    photosynthesis is extremely slow due to the very slow diffusion of enzyme and substrate molecules through the ice lattice. Therefore I can make a firm prediction that for this particular investigation, the volume of oxygen produced will be rather small as oppose to being zero.

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

    alters the shape of the active site, thus a better more tight fit. Once the products have been released, the enzyme and active site returns to its original shape. The main reason for enzyme controlled reactions is to lower the activation energy of a reaction.

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

    Photosynthesis is the process of converting light energy into chemical energy which can only be performed by plants. All life on earth depends upon the ability of plants to photosynthesize simple sugars which are the basic source of food from which all other forms of food originate.

  1. How temperature affects the rate of photosynthesis.

    Different substrate molecules called inhibitors have shapes similar to the active site of the enzyme molecules and can block the active site, thereby making the enzyme ineffective. All these factors including temperature have an impact on how the enzymes work and therefore the rate of the reactions controlled by the enzyme.

  2. Investigate one factor which will affect the rate of photosynthesis

    I could see this from the graph that was produced: (P.T.O for graph) From the graph it is clear that the more the light intensity was decreased, the less O2 was produced. However, I also know that if the light intensity was too great the chloroplasts would be damaged and therefore unable to perform photosynthesis.

  1. The aim of my investigation was to determine how limiting factors would affect the ...

    Opening of the stomata not only allows CO2 to diffuse into the leaf, but allows water to diffuse out of the leaf. The alteration in the size of the stomata occurs in response to a variety of the external stimuli such as light, carbon dioxide concentration and water.

  2. What factors affect the rate of photosynthesis?

    The area between membranes (thykaloids, grana) inside the chloroplast. Thylakoids: The specialised membrane structures in which photosynthesis takes place. They are the internal membranes in the chloroplast where the light reaction chemicals (prokaryotes and eukaryotes) are embedded. Collections of Thylakoids form the grana What happens in the light reaction?

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