Introduction
Enzymes are proteins the act as biological catalysts. It increases the rate of reaction chemical reactions by decreasing the amount of activation energy. Some examples of enzymes are digestive enzyme, food enzyme and metabolic enzyme. Salivary amylase is an example of digestive enzyme which is involved in breaking down of large molecules into simpler ones by the process of hydrolysis. Enzymes have specific shapes that allow specific substrates to fit in and if it loses its shape it can no longer accept a substrate and produce products. Many enzymes need cofactors to function. (Marieb, 2001)

The activity of enzymes is strongly affected by changes in pH and temperature. Each enzyme works best at pH 7 and temperature 370C in human body. Extremely high or low pH values generally result in complete loss of activity for most enzymes. An enzyme will denature if the pH level is too low or too high. The bonds in the enzyme break and the enzyme loses its shape and it can no longer do its task. Many enzymes are adversely affected by high temperatures. High temperature often causes permanent damage to the molecular structure of enzymes therefore the enzymes become denatured. Some enzymes lose their activity when frozen. (Worthington, 2010)
Enzyme activity is measured using spectrophotometer. An increase in light absorbancy will indicate that molecules have been broken down by enzymes. (Sinclair, 2010)

The purpose of this investigation is to examine how the adverse conditions like temperature and pH affect enzyme salivary amylase to carry out its function. This is important because enzymes work best within a very narrow range of pH and temperature so if the conditions does not fall in this range the enzyme will not operate and will have difficulty in absorption of nutrients in patient who are deficient of the particular enzyme and it is also important because enzymes increases the speed of reaction and if there are no enzyme the reaction rate will be slow which can cause hindrance to patients physiology. (Cree & Rischmiller, 2003).
Method
A pipette was set to the approximate measurement to ensure that it transferred 50 ul of the sample. Gloves were worn. A disposable pipette tip was attached to the pipette shaft. A curvette that had been incubated at 370C was taken. 50 ul of saliva sample at pH 3 drawn into the tip of pipette by gently pushing the thumb on the plunger until the first stop was felt. Holding the pipette vertically, the tip of pipette was immersed in amylase reagent in the curvette ensuring not to touch the bottom of the curvette with the pipette tip. The thumb was slowly released so that the plunger returns to starting position. To release fluid, the end of the pipette tip was placed on the side of the curvette. A pipette was kept in vertical position but the curvette was turned on a slight angle. The plunger was pushed gently to the second stop and saliva was released. Stopwatch was immediately started as the saliva was released into the curvette. Pipette tip was released into the virkon dish by holding the pipette over the dish and pushing down on the tip of ejector. Curvette was covered with parafilm. The curvette was gently inverted to mix the solution by placing it between the thumb and finger. Curvette was taken to spectrophotometer and parafilm was removed. Curvette was placed in spectrophotometer making sure that clear side of the curvette was facing the light. The absorbance was read at 405 nm at 60 seconds and 2 minutes without stopping it in between these times. The results were recorded in the table. Curvette was disposed in virkon dish. Above procedure was repeated for same temperature and same pH. Same procedure was followed for pH 7 and temperature of 800C. Other parts of the lab were done by the other groups due to time factor. Mean of all the results obtained by each group were recorded under results. After the experiment, clean up was done and the apparatus were placed at