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

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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.

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