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

How does a change in temperature effect the activity of the catalase enzyme on a piece of liver?

Extracts from this document...


BIOLOGY COURSEWORK INVESTIGATION How does a change in temperature effect the activity of the catalase enzyme on a piece of liver? PLANNING Background knowledge An enzyme is a biological catalyst; it alters the rate of reaction without being changed itself. Enzymes are proteins; they have a very precise three- dimensional shape, which forms a one specific active site on the enzyme. Each enzyme can only convert one kind of substrate molecule into one kind of product molecule. What affects Enzymes? - Temperature - Enzymes start to denature if the temperature rises above 37.5 C Increasing the temperature alters the three - dimensional shape of the enzyme therefore the enzyme can no longer fit the substrate - pH - Enzymes work best in neutral conditions neither acidic or alkaline. What effect does catalase have? Catalase is a very fast reacting enzyme, it is found in many living cells, it breaks down hydrogen peroxide to water and produces oxygen. In fact one molecule of it can deal with six million molecules of hydrogen peroxide in 1 minute. Hydrogen peroxide is toxic so it needs to be changed into harmless substances. The equation for the reation: 2H202 Catalase 2H20 + 02 Reference to praticals referring to enzymes - Biology for You Pg. 30 - Experiment 3.1 From looking at this I found that the catalase reacts with the hydrogen peroxide to give out water and oxygen. ...read more.


- Take the measurements of hydrogen peroxide and water at eye level and on an even surface and with a 90-degree angle to the lab bench from the measuring cylinder. - Take each reading three times to ensure that there isn't and anomalous result. Three is a good number to use as you can see the if there is an anomaly whereas if I was to take each reading twice I wouldn't be able to distinguish the anomaly. Also I am able to obtain an average. To make sure I am carrying out a safe experiment I will make sure that I am wearing safety glasses, as the hydrogen peroxide is corrosive and an irritant. I will also carry out any other safety precautions e.g. hold hot beaker with tongs. Prediction Taking into account my research I believe that the amount of gas given off by the reaction will increase as I increase the temperature that the reaction takes place in. The amount of gas given off will start to decrease after 37.5C and any other temperature above that. This is because the enzyme is denaturing. Reason being that enzymes are proteins and their structure is three dimensionally. Increasing the temperature disturbs the intra - molecular bonds that hold the 3D shape. As a result of this the shape has been altered. Enzymes have an active site. This fits into the substrate molecular. If the active site is altered the substrate will no longer fit in and so the enzyme doesn't work properly. ...read more.


- I would take longer to carry out the experiment and achieve more results, therefore improving the accuracy of my results. - As well as changing the temperature at which the enzyme works I would also change the weight of the liver piece. I would investigate if the change in temperature has more of an effect than the amount of enzyme present. - I would maybe take more results (5 tests) to give me even more reliable evidence and a more accurate average. - I would see how temperature effects other enzymes such as pepsin or trypsin, which bring about the digestion of meat - I would investigate the effect of enzymes in different conditions (changing pH levels). There isn't really another way of carrying out this experiment, except for using the suggestions and improvements that are above. What would be the most interesting extension to this work is to see what pH conditions the liver enzyme works best in. Diagram I would use different pH levels and measure have much oxygen gas is given off. I would use the same procedure for the method above, but I would use different pH levels instead of the hydrogen peroxide. I wouldn't apply heat at first I would just see which pH level the liver enzyme works best in and maybe apply heat to that. I wonder if I would see the same effect? ...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 Molecules & Cells 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 Molecules & Cells essays

  1. Marked by a teacher

    The effect of temperature on catalase activity

    3 star(s)

    When enzymes denature the heat starts to destroy their shape and structure. The shape of the enzyme is so important to its working that any change in the shape of the molecules will make them less effective or stop them working completely.

  2. Investigate how concentration of the enzyme catalase in celery tissue alters the rate of ...

    These are inconsistent results, but by calculating the gradient of the last section of these two lines, I hope to show that the anomalous results are not useless. Gradient = increase in y-axis-direction increase in x-axis-direction So, Gradient of line between 2 and 3 minutes for 75% Celery Extract concentration

  1. Reaction of Catalase and Hydrogen Peroxide

    Than I had used the pipette to take 4 ml of hydrogen peroxide from the beaker and put it in the boiling tube. Like in the measuring cylinder I had taken the lower meniscus and also made sure that I don't take in hydrogen peroxide by mistake.

  2. Investigating the effect of the Temperature on the Enzyme Catalase when it reacts with ...

    I have good scientific knowledge, which can help me through out this experiment, because this will make the task much easier to do. Before hand doing this experiment we were given the reaction that catalase speeds up. Hydrogen peroxide Water + Oxygen The substrate that catalase recognises was the Hydrogen Peroxide, and the products formed are Water and Oxygen.

  1. The effect of Copper Sulphate concentration on Catalase activity on Hydrogen Peroxide.

    HoIver the actual pH at which each group becomes ionised depends on the particular amino acid and also the environment in which the enzyme is found. The usual way of expressing this is the pK value: this pK is the pH at which half of the groups are ionised.

  2. for this experiment my main aim is to investigate the effect of temperature on ...

    binds only briefly to the active site then there is competition between it and the substrate for the site, but if there is much more of the substrate than the inhibitor present, the substrate molecules can easily bind to the active site in the usual way and so the enzyme's function is unaffected.

  1. Investigating the Catalase Activity in Calf and Ox Liver

    Hypothesis The catalase activity in calf liver is higher than the catalase activity in ox liver. I believe this to be the case, because as a calf is younger than an ox, its liver has been subjected to less damage due to natural wear and tear, and infections, so generally

  2. Investigating the effects of Copper Sulphate on the action of Catalase Enzyme breaking down ...

    4.0 12 0 8 56 1.2 2.1 3.6 4.7 5.6 7.0 From my preliminary results I can see that I have quite a good range of readings. I have discovered that even small quantities of copper sulphate can slow down the rate of the reaction drastically, so I have decided to use only a maximum of 1ml of copper sulphate.

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