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

How does the concentration of a carbohydrate affect the rate of respiration?

Extracts from this document...

Introduction

HOW DOES THE CONCENTRATION OF A CARBOHYDRATE AFFECT THE RATE OF RESPIRATION? PLAN: Aim: The aim of this experiment is to find out which carbohydrate produces the most energy in respiration. For this I have to find out which carbohydrate is best. Prediction: Once the best carbohydrate is found, we can vary different factors to find out if the carbohydrate works best in different conditions. In this case I will change the concentration. From this I can predict that the higher the concentration, the carbohydrate will produce more energy. The greater the concentration of the carbohydrate the more carbon dioxide, water and energy will be released. My reason for this prediction is that yeast is a unicellular fungus, which feeds saprophytically and can respire both aerobically and anaerobically. In the experiment the yeast will be respiring anaerobically and breaking down the glucose stored in it as a waste product of this process it will also form CO2 and alcohol in the form of ethanol. This respiration process is called fermentation. The yeast breaks down the glucose using a series of enzymes. Hypothesis: Which carbohydrate is used up most by yeast? ...read more.

Middle

These days were then made up. This experiment was performed fairly the only factor that may have been unfair was the fact we missed two days readings, although when we made them up the results seem to be fair. This experiment was very safe as well nothing was out of place and everybody work sensibly. There isn't any reason why it shouldn't be safe for people watching. Once the sucrose solution has been added to the beakers the yeast will be added into the beakers. Once that has been completed and everything has been added you mass each beaker and record the results. It would be better to take the readings three times each so that you can average them out and so fairer results can be taken. Water should be added to the u-bend of the tube to stop other gasses getting into it. If this did happen then it would affect the mass. The conditions that will be kept the same are the temperature of the surroundings, and the amount of yeast that would be added. Also making sure that the yeast came from the same cause. ...read more.

Conclusion

Well the mass loss of the 20% concentration was less then the 1% concentration on the first and second day. This does seem strange because the 20% would have respired quicker than the 1%. This might have happened because of a few things. One may have been subject to more light or have been shaken more than another. This does increase the kinetic energy and so the molecules would be bumping into one another increasing the chance of entering the yeast cell. This experiment I feel has been carried out very well and so is very reliable. Maybe to have made sure we could have put the beakers into a heating bath to make sure the temperatures were the same. Although this might not have made any difference the results might have still shown the same outcome. To extend this further I could use different types of yeast, maybe the next better carbohydrate at respiration, this being maltose. As I said before using other concentration possibly going higher to find trends, 25% or 30% concentration. Different pH's could be tried out because different carbohydrates work at different optimums. To find out how much has been produced we can use a gas syringe, which would hopefully make it more reliable. Harry Bowman 11f Mr Robinson Biology coursework ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Exchange, Transport & Reproduction 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 AS and A Level Exchange, Transport & Reproduction essays

  1. Peer reviewed

    "An investigation into the Respiration of Carbohydrate Substrates by Yeast."

    5 star(s)

    The theory states that if temperature is increased the particles gain more energy and there are more collisions in a given time. Similarly, increasing the concentration means than there is a higher chance of a collision happening because there are more particles in a given volume.

  2. Peer reviewed

    Effect of Caffeine on the Heart Rate of Daphnia

    3 star(s)

    is done in 15 seconds. Only Daphnia (sp.) is used throughout the experiment. Throughout the experiment, the Daphnia are kept only in pond water or mixture of pond water and caffeine solution. Technique: In this experiment, x techniques are applied to conduct this experiment. The x techniques are as follow: 1.

  1. Rate of Respiration

    I will heat the water bath to 40C because I have decided to use this temperature for my experiments. I will prepare substrate solution by adding 0.8M of sugar to 20cm3 of acidic buffer solution, and pour the solution into a boiling tube.

  2. An investigation to see whether the concentration of Sucrose effects the amount of Carbon ...

    concentrations of the sucrose solutions can be tested at the same time. The sucrose solution will be added to the beaker first, and then the yeast is added to the beaker. The beakers should be labelled with the concentration of sucrose they have inside so the results don't get mixed up.

  1. Investigate one factor that affects the rate of respiration of yeast

    Range: I will take 5 readings (total of 15 because I take 3 measurements of each reading). Initial glucose solution concentration will be 2% and with increments of 2% concentration, the final glucose solution concentration I will test is 10%.

  2. To find out the factors affecting the refractive index of liquid by using different ...

    Even if I raised the temperature, the molecule moved faster but they are still moving around randomly. The speed of light only change very little with increasing temperature. The design of the experiment should be more precise in order to detect that little change.

  1. Rate of respiration in Yeast.

    Plan: I intend to count the number of bubbles that appear in a test tube of water when I mix yeast with glucose or sucrose. The number of bubbles that appear will tell me the rate of respiration in the yeast.

  2. Investigate the effect different concentrations of glucose in a yeast & Glucose solution has ...

    Method Make sure the environment is safe to perform an experiment. Do this by clearing the working surfaces of obstructions and making sure the area around your feet is tidy. It is also necessary to wear safety glasses for the duration of the experiment.

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