Induced Fit Model

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Discussion Enzymes are used to speed up biochemical reactions that occur within the body. They act as a catalyst for specific substances and therefore reduce activation energy. A catalyst is a substance that speeds up the rate of a chemical reaction without being used up or altered, and therefore can be used repeatedly. Enzymes are also used to control cell metabolism by regulating the rate of biochemical reactions, this is because the amount of enzyme in a solution determines how fast a reaction can occur. An enzyme consists of complex chemicals that form precise, tertiary and quaternary protein structure consisting of long, linear chains of amino acids linked together with polypeptide bonds, which fold in such a way that they form a…show more content…
This theory states that the shape of the active site changes to the correct shape when the substrate binds to the enzyme. When the products of the reaction are formed, they no longer fit the shape of the active site and fall away from the enzyme active site. The enzyme then reverts back to the original shape, until another substrate molecule collides. Below is a diagram showing the induced-fit model. Both models show why enzymes are not changed by the reactions that they catalyse and provide an explanation as to why enzymes can be continually re-used. They are able to bind to the substrate to allow a reaction to happen but they do not go through any chemical change…show more content…
Below is a table showing the rate of reaction as the concentration of substrate is increased. The rate of reaction will increase as the concentration of substrate increases due to the increase in potential of a substrate colliding with an enzyme. You can see by looking at the graph that the rate of reaction will increase until the enzymes become saturated, the enzymes reach maximum productivity. All active sites are occupied. Product cannot be formed any quicker as maximum efficiency as been reached and the only way to increase the rate of reaction any further would be to increase the concentration of enzymes. There are also substances that can slow down the rate of reaction, or prevent the formation of enzyme-substrate complexes altogether. The process is known as inhibition and the substances that are used are known as inhibitors. There are two main categories of inhibitors; there are competitive inhibitors and non-competitive inhibitors. Inhibition is usually reversible, when the inhibitors are removed the enzymes return to full
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