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Enzymes Investigation

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Enzymes Investigation Scientific background- Enzymes are long chains of protein but not all proteins are enzymes. They can be folded into all kinds of shapes. Each enzyme has a very special shape, which acts as a catalyst. They speed up the breakdown of large molecules to smaller molecules. For an enzyme to work they first must collide with its substrate. The more energy molecules have the faster they move and vibrate, this energy makes more collisions. When a successful collision occurs the enzyme fits into its substrate using the lock and key method. Each enzyme is a particular shape and acts as a lock. Into the enzyme fits certain molecules like a key. The enzyme begins to break down the molecule once this has happened. When the molecule is broken up the enzyme remains the same shape. ...read more.


This means more are successful, and it is more reactive. In the practical I will also use hydrogen peroxide, which is a chemical that breaks down into water and oxygen. Fair test- I will change one variable during the practical and to make it fair. This variable will be the temperature. I also kept some variables the same: * I will keep the concentration of the hydrogen peroxide at 10VOL. * I will keep the amount (10ml) of hydrogen peroxide in each test tube the same. * I will keep the weight of the potato the same (2 gram). * I will keep the amount of drops, of detergent the same (2-3 drops). Also to make the practical a fair test I will measure everything at eye level. Safety- During the practical I will be using hydrogen peroxide, which could be potentially harmful. ...read more.


I conclude that catalase breaks down hydrogen peroxide into water and oxygen at 40�C. It works best at this temperature, as this is the enzymes optimum temperature. Catalase gets enough energy at 40�C to make the molecules move quickly. The quicker the molecules move the more chance there is of them making a successful collision. When a successful collision occurs the substrate fits into its enzyme like a key into a lock. When the substrate is in the enzyme, the enzyme breaks the substrate down. Evaluation- I found one anomalous result during the practical. I found this in my 0�C test where the height difference were much higher than I expected. They were higher because the fridge door was left open and the thermostat was at a higher temperature than 0�C. This higher temperature made the enzymes work better than they would at 0�C because the higher temperature resulted in more successful collisions. ...read more.

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