Report+on+Investigating+the+effect+of+temperature+and+PH+on+enzyme+action+experiment

Aim: To investigate and find out the effect of temperature and PH on enzyme action.

Predictions: -The higher the temperature of the solutions the higher the rate of enzyme action. -The PH value of the solutions affects the attraction between the substrate(starch) and the enzyme(amylase) which then affects the rate of enzyme action.

Assumptions:

Difficulties encountered: -It was difficult to maintain the temperature of the mixtures of some of the test tubes at exactly 37 degree celsius at warm water had to be poured in to the beaker which the test tubes were placed in every minute or so to ensure that the temperature of the test tubes remained at 37 degree celsius. -The time given to complete the experiment was tight and thus, time-management to make sure the experiment was completed int he given time frame was also one of the difficulties encountered.

Precautions taken: -Precaution was took to ensure that the solutions was not contaminated as it would affect the results of the experiment. Thus, the dripper had to be washed after every use. -Also, the timing of the experiment was crucial and great precaution was taken to ensure that the timing was accurate so as to be able to achieve accurate results.

Observations and results:

__Part A__
 * < Temperature (degree celsius) ||< Test Tubes ||< Iodine test results ||
 * < 0 ||< A1,A2 ||< blue-black ||
 * < 37 ||< B1,B2 ||< brown ||
 * < 100 ||< C1,C2 ||< blue-black ||
 * < 37 (control) ||< D1,D2 ||< blue-black ||

-Test tube B showed that starch digestion has occurred as it did not turn blue-black after the iodine test thus showing that the starch that was placed in the test tube before the experiment was digested. -Test tubes A and C contained mixtures that gave a blue-black colour. -The mixture in tes tubes A and C remained blue-black as starch digestion did not occur due to the extreme temperatures of the mixture. -Test tube D served as a control for the experiment. As distilled water and starch was placed into it, it can be used to ensue that the starch would turn iodine solution blue-black without being digested as distilled water is not an enzyme, unlike amylase that was used in the other test tubes. -The iodine test when used on the mixtures tells us whether the mixture contains starch. Iodine indicates the presence of starch when it turns from brown to blue-black. -The temperature of the substrate and enzyme does affect enzyme action.

__Part B__ -2cm3 of amylase -2cm3 of HCL || blue-black || -2cm3 of amylase -2cm3 of distilled water || brown || -2cm3 of amylase -2cm3 of NH4OH || blue-black || -4cm3 of distilled water || blue-black ||
 * Test tube || Contents || Iodine test results ||
 * W || -2cm3 of starch
 * X || -2cm3 of starch
 * Y || -2cm3 of starch
 * Z (control) || -2cm3 of starch

-Test tube X shows that starch digestion has occurred as it remained brown after the iodine test thus showing that the starch that was placed in the test tube before the experiment was digested. -Test tubes W and Y contained mixtures that gave a blue-black colour. -The mixtures in test tubes W and Y remained blue-black as starch digestion did not occur due to the extreme PH values. Hydrochloric acid is too acidic while ammonium hydroxide is overly alkali. -When the PH value of the solution is overly high or low, enzyme action will not occur.

Conclusion (and analysis): -Both the temperature and the PH value affects enzyme action, However, the temperature and PH value can not be too extreme as it would then not be suitable for enzyme action to occur. -In conclusion, enzyme activity is greatly affected by changes in the PH value and temperature. Enzyme activity is the most "active" at certain PH values and temperature and the rate of its activity decreases above and below that point.


 * Ms Tan, i could not figure out how to type the 2cm3 thing even after trying and asking many people and somehow, i could not copy it over from the net so i typed it the way it is. Sorry!