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

Planning an experiment to investigate the effect of an enzyme on the rate of hydrogen peroxide breakdown.

Extracts from this document...


Planning an experiment to investigate the effect of an enzyme on the rate of hydrogen peroxide breakdown Aim To investigate the effect of celery extract concentration on the rate of hydrogen peroxide breakdown. Question: What is the most efficient concentration of celery extract enzyme to breakdown the solution of hydrogen peroxide into water and oxygen? Apparatus Hydrogen peroxide solution Celery extract solution Stand Clamp & boss 6 Test tubes Stopwatch Test tube rack 150cm conical flask + bung + tubing + 3 way tap Tubing Through Gas syringe Balance Goggles Labels Hydrogen peroxide Hydrogen peroxide will breakdown to oxygen and water in the presence of catalase. The reaction will increase with increasing enzyme concentration when molecules of hydrogen peroxide are freely available. However, when molecules of the substrate are in short supply, the increase in rate of reaction is limited and will have little effect. Celery extract (catalase) This important enzyme in present in all aerobic tissues (Vines and Rees, 1969). Since hydrogen peroxide is toxic to protoplasm it must be broken down into water and molecular oxygen. ...read more.


Inhibitors therefore slow the rate of reaction. They should not have affected this investigation, however, as none were added. The volume of catalase solution will not be changed as well. So the temperature, inhibition, substrate concentration, and volumes of enzyme are kept constant So that it is a fair test. Method 1. Make the concentration of 20%, 40%, 60%, 80% and 100% of celery extract solution. I want use 4ml of celery extract and 16ml of water as 20% of celery extract solution, 8ml of celery extract and 12ml of water as 40% of celery extract solution, 12ml of celery extract and 8ml of water as 60% of celery extract solution, 16ml of celery extract and 4ml of water as 80% of celery extract solution, and 20ml of celery extract as 100% celery extract solution. Pour each one of the solutions in a test tube, and place them on the test tube rack. To make sure that the concentrations are accurate, a syringe or a measuring cylinder will be used to measure the volume. ...read more.


This allows you to perform the experiment safely and unimpeded care should be taken to ensure that liquid is not spilled onto the floor to cause slippage. Prediction The enzyme molecules have active sites that help them to recognize their substrates in a very specific way. Just like a key only fits into a specific lock, each enzyme has its own specific lock, each enzyme has its own specific substrate. This is called the lock and key theory. The enzymes never actually get consumed in the process; they just increase the rate of reactions. I think the concentration of 100% of enzyme solution will produce 30ml of oxygen gas by the shortest time, because it has more enzyme molecules than other solutions, in the plant the enzyme is undiluted, and therefore the most efficient solution is likely to be 100%. Conclusion A preliminary test was carried out to practice the techniques of measuring small volumes with the syringe and making accurate concentration of enzyme. It was also beneficial, because some problems were encountered with the assembly of the equipments, which would have had a negative effect on the experiment if they had not been detected beforehand. 1 ...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

    Investigating the breakdown of hydrogen peroxide using celery tissue to supply the enzyme catalyst

    4 star(s)

    I know that the reaction is catabolic; therefore it will produce two substances. These are water and oxygen. Measuring the volume of oxygen can be done in various ways, counting the bubbles, collecting the gas and measuring its volume or collecting the oxygen over water.

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

    * I then recorded my results into a table in order for me to be able to produce a graph. Diagram of the apparatus: Risk assessment: Apparatus How can it be dangerous How to prevent Hydrogen peroxide It is a harmful and irritant substance, if it gets in contact with the skin, it will react with it bleaching its colour.

  1. To investigate the rate at which hydrogen peroxide is broken down by the enzyme ...

    therefore an enzyme molecule will hit a substrate molecule more frequently and cause a reaction when the substrate successfully collides with the enzyme's active site. When the enzyme is less concentrated it is less likely that the enzyme molecules will hit a substrate, as frequently and therefore there will be

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

    If any enzyme inhibitors are present then the overall rate of reaction would be much slower than a reaction without. The velocity-time graph would still show a similar correlation to the graph above, as the amount of enzyme inhibitors is finite and does not speed up with time.

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

    From the practical experiment that I have done I have gained all the results for all the different temperature, I have also found out the optimum temperature where the enzyme catalase works suitably and also found out the temperature where the enzyme catalase denatures.

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

    > Prepare stop watch. > Place liver into the conical flask and immediately close the top of the conical flask with rubber stop from the syringe. > As soon as that is done, start your stop watch and take readings on the syringe at desired time interval.


    of enzyme molecules in a reaction, there will be more empty active sites available for the substrate to bind with. More enzyme- substrate complexes shall form resulting in an increased rate of reaction. So, as you increase the no. of enzymes, the rate of reaction increases.

  2. This is an experiment to show how different concentration of celery tissue enzyme, catalase ...

    The hypothesis suggests that when the enzyme's active site comes into contact with the right substrate, the active site slightly changes or moulds itself around the substrate for an effective fit. This shape adjustment triggers catalysis and helps to explain why enzymes only catalyse specific reactions.

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