>The science behind it all
Structure and Function of an Enzyme
Enzymes are large proteins that speed up chemical reactions. In their globular structure, one or more polypeptide chains twist and fold, bringing together a small number of amino acids to form the active site, or the location on the enzyme where the substrate binds and the reaction takes place. Enzyme and substrate fail to bind if their shapes do not match exactly. This ensures that the enzyme does not participate in the wrong reaction. The enzyme itself is unaffected by the reaction. When the products have been released, the enzyme is ready to bind with a new substrate.
This information is Courtesy of ENCARTA ENCYCLOPedia
>introduction
what is yeast ??
Yeast, any of a number of microscopic, one-celled fungi important for their ability to ferment carbohydrates in various substances. Yeasts in general are widespread in nature, occurring in the soil and on plants. Most cultivated yeasts belong to the genus Saccharomyces; those known as brewer's yeasts are strains of Saccharomyces cerevisiae.
What is fermentation ??
Fermentation, chemical changes in organic substances produced by the action of enzymes. This general definition includes virtually all chemical reactions of physiological importance, and scientists today often restrict the term to the action of specific enzymes, called ferments, produced by minute organisms such as moulds, bacteria, and yeast’s. For example, lactase, a ferment produced by bacteria usually found in milk, causes the milk to sour by changing lactose (milk sugar) into lactic acid. Probably the most important type of fermentation is alcoholic fermentation, in which the action of zymase secreted by yeast converts simple sugars, such as glucose and fructose, into ethyl alcohol and carbon dioxide. Many other kinds of fermentation occur naturally, as in the formation of butanoic acid when butter becomes rancid and of ethanoic (acetic) acid when wine turns to vinegar.
Generally, fermentation results in the breakdown of complex organic substances into simpler ones through the action of catalysis. For example, by the action of diastase, zymase, and invertase, starch is broken down (hydrolysed) into complex sugars, then simple sugars, and finally alcohol.
What are enzymes ??
Enzyme, any one of many specialized organic substances, composed of polymers of amino acids, that act as catalysts to regulate the speed of the many chemical reactions involved in the metabolism of living organisms. Identified enzymes now number more than 700.
Enzymes are classified into several broad categories, such as hydrolytic, oxidising, and reducing, depending on the type of reaction they control. Hydrolytic enzymes accelerate reactions in which a substance is broken down into simpler compounds through reaction with water molecules. Oxidising enzymes, known as oxidises, accelerate oxidation reactions; reducing enzymes speed up reduction reactions, in which oxygen is removed. Many other enzymes catalyse other types of reactions.
Individual enzymes are named by adding ase to the name of the substrate with which they react. The enzyme that controls urea decomposition is called urease; those that control protein hydrolyses are known as proteinases.
This information is courtesy of larouse desk reference encyclopedia
>evaluation
after all the experiments were complete we conferred our results with fellow classmates and there does not seem to be any sight of anomalous results.
My prediction fits into the trend of the graph. I stated that “when the concentration of glucose is 0ml that the amount of carbon dioxide will be extremely low”. And as shown in the graph the last three results were 0.3, 0.4, and 0.2, which are low.
Errors: this could happen if there is pressure in the glass tube before the experiment. Which would then cause a burst of air to rise up the burette and cause a major drop in the results.
>what could be improved ??
The improvements that could be made to this investigation are: the beaker could be placed upon a form of vibrating plate to shake the solution and keep it flowing, this should then able the solution to release all the carbon dioxide. Another improvement that could be made is to replace the large round plastic bowl with a glass/plastic tank. These minor improvements could make the next investigation a bit more reliable and more accurate.
By Adam Lenihan
