How temperature effects the hydrolysis of starch with amylase as it's enzyme.

How temperature effects the hydrolysis of starch with amylase as it's enzyme.

Biology AS course work on Enzymes:

Aim: To investigate the effect of temperature change on the rate of hydrolysis of starch catalysed by amylase.

Hypothesis: Temperature change (positive) will almost certainly have the effect of catalysing the starch which is being catalysed by the amylase solution, meaning it will speed up the entire reaction which is already being catalysed. Enzyme activity will be profusely affected whatever the temperature change is.

Science Reasoning For Hypothesis: Proteins have biological catalysts (a substance which speeds up the reaction without becoming part of the product). They are called enzymes which when binding to the reactants of the reaction they're catalysing, cause the amount of activation energy to decrease, causing the reaction's speed to increase. A large activation energy amounts to a slower reaction because the substrate needs to surpass the initial activation energy, so a lower one will result in a faster reaction. An enzyme and a product are left at the end of a chemical reaction with a substrate and reactant. Interactions between enzymes and substrates are noticeably weak, so a large surface area is usually required, this is to increase the chances of reactions. Metabolic reactions are also catalysed by enzymes such as respiration and digestion (of foods) they're also receptors and membrane pumps amongst many other proteins (every single metabolic reaction). Amylase is a globular protein as all enzymes are, the active site being where the reaction takes place.

The reaction rate will almost always increase at optimum temperature - but only up to the optimum temperature, which is in exact proportion to the temperature rise. This is because both the substrate and enzyme molecules in any particular reaction have more kinetic energy, therefore the particles have a higher chance of actually colliding with one another (so reaction speed increases).

The Substrate molecule is held in position by amino acids which occupy the a certain space in the active site - this occurs whilst the reaction is in progress. Any other molecules simply won't fit into the active site - the enzyme's specific purpose is for one sole reaction - molecules of a different shape simply won't connect to the active site. The enzyme will then speed up the reaction on it's surface, the product is then released. All chemical changes cause a product to be formed from a substrate.

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