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

Investigate how light intensity affects the rate of photosynthesis.

Extracts from this document...

Introduction

Biology SC1 Introduction Plants also take in energy, like humans, who get their energy from raw materials-such as food, however plants do not seem to be in taking food their mostly common source of raw materials comes from the soil. A statement from GCSE Biology states'...Experiments show that the weight gained by a growing plant is far greater than the weight lost by the soil it is growing in.' This statement implies that there must be an increase in the raw materials such as water and air. A hypothesis to show a source of food in plants is from the air, water and soil salts. Glucose contains three elements carbon, hydrogen, and oxygen (C6H12O6). The carbon and oxygen is mainly supplied by (CO2) from the air and the hydrogen from water (H2O), in the soil. What is photosynthesis? Photosynthesis the building up of complicated food molecules from simple substances better known as 'synthesis.' In order for this process to take place, it requires enzymes and energy. The first stage where synthesis begins is from the sun. The sun supplies the plant as a source of light, which is essential for photosynthesis. This is where we get the word 'photo' from as it means 'light'. ...read more.

Middle

Method > Collect the above apparatus. Make sure they are washed in clean water using detergent as otherwise bubbles may stick to the apparatus. > Using a measuring tube collect 10cm3 of sodium hydrogen carbonate. > Add it to250cm3of water (H2O) The reason for this is to maintain the level of carbon dioxide (CO2) > Collect 5cm of Canadian pondweed (Elodea) > Place this into a beaker but DO NOT PUT IT IN THE WATER AND NaHCO3 SOLUTION JUST YET! > The reason for this is because the rest of the apparatus has not been set up and it will make the results unreliable. > Attach the photosynthometer to the stand + clamp. > Set it up as shown in the diagram. > Keep the metre stick in a secure place avoid it from moving. (A suggestion you keep it stuck down by using a bit of masking tape at the bottom of it.) > Have the lamp ready to switch on. BUT NOT YET! > When ready put Elodea in the solution (water and NaHCO3) and attach it to the micro-burette. > Turn on the lamp, which should be at the appropriate distance on the meter stick. ...read more.

Conclusion

Instead of using the sophisticated apparatus: photosynathermetre and the graduated capillary tube I could have simply used a beaker, test tube, stop watch, a lamp, a metre stick and the same solution (water and NaCHO3). However this experiment would have been inaccurate because I would have had to count the bubbles myself and measure the gas quantity. The other disadvantages I may encounter would be the following: > When the lamp is at its furthest distance (100cm) from the Elodea the bubbles are going to reduce by quantity and size, therefore the bubbles maybe too small to see which would have made them difficult to count as a result. > The lamp could be too close to the test tube and heat up the water quickly making the temperature to be inaccurate and the rate of photosynthesis would vary. > When the lamp is at its closest distance (0cm) from the Elodea the bubbles are going to be rapidly produced therefore once again making it difficult to count. > If the lamp heated the water up, the temperature would have increased giving me two limiting factors: temperature and light intensity, instead of just one. This would have gone against my hypothesis. > The whole experiment would not be as accurate as the photosynthometer. The main advantage in using the above apparatus' has been that it is easy to set-up and use. ...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. This experiment involves using a photosynthometer to investigate how temperature affects the rate of ...

    The energy released by the motion of the electron is used to synthesis ATP. Followed by cyclic phosphorylation comes non-cyclic phosphorylation, in which both of photosystems 1 and 2 are involved. Light is trapped by both photosystems and electrons emitted by both primary pigments (P700 and P600).

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

    also so all the leaves fit into the hydrogen carbonate solution so that all the leaves receive the same amount of carbon dioxide. * The experiment should be repeated 3 times and averaged to ensure the experiment is as reliable as possible to ensure a conclusion can be firmly supported.

  1. The aim of my experiment is to find out how light intensity affects the ...

    Above that temperature, the enzymes begin to denature, slowing the rate of photosynthesis until a temperature is reached where photosynthesis does not occur at all. Photosynthesis and respiration To unlock the energy in the carbohydrate produced in photosynthesis, green plants need to respire, just as animals do.

  2. How temperature affects the rate of photosynthesis.

    This occurs due to the hydrogen bonding between the different amino acids present in the chain. The tertiary structure is formed when the secondary structure of the protein (enzyme in this case) is coiled and folded up to from a precise 3 dimensional shape.

  1. INVESTIGATING HOW TEMPERATURE AFFECTS THE

    After measuring 20cmand checking that the water has fallen to the required temperature I will transfer it into the test tube. I will again use forceps to drop the beetroot into water and start timing as soon as the beetroot is in.

  2. What affects the rate of photosynthesis in Elodea?

    Chlorophyll is green because it can only absorb the red and blue lights at either end of the visible spectrum, it reflects off the green light in the middle because it cannot be absorbed. If we put a light with a green filter to the elodea the plant would not

  1. Find out how the amount of light, that is light intensity, affects the rate ...

    Temperature- the optimum temperature is around 30 . Photosynthesis still works fine up to about 40 . But once you get much above 40 it slows down dramatically. Carbon dioxide- if paraffin is burnt in a greenhouse the carbon dioxide levels increase and so does the rate of photosynthesis- that increases growth.

  2. The aim of our investigation is to find out how the amount of light, ...

    You must have ACTUAL results from your preliminary experiment, not predicted ones. What information does your preliminary experiment provide that can be used in your full experiment? What EXACTLY was the purpose of the preliminary work? Distance (cm) Light intensity (lux)

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