Read without ads. Stee eer an AIM “ To study the digestion of Starch by salivary amylase and effect of temperature and pH on it.” Download SCRIBD Download any document, ad-free. ST CUE RecsRead without ads. Te ee an Start Free Irial Cancel Anytime. Objective of the Project Report The main objective of this chemistry project report is “To study the digestion of starch by salivary amylase and effect of temperature and pH on it” . 1. To study the digestion of starch by saliva. 2. To study the effect of temperature on the digestion of starch by saliva. 3. To study the effect of pH on the salivary digestion of starch. & SCRIBD Download any document, ad-free. STUER keyRead without ads. Stee eer an Introduction Every health book insists on the chewing of food. The act of chewing stimulates the excretion of saliva. Saliva mixes up with the food and helps its digestion. That is, the enzyme ptyalin or amylase present in human saliva hydrolyzes the big molecules of food into many molecules. For example, starch into mono-saccnaricies maltose and glucose; proteins into amino acids and fats into fatty acids and glycerol. Thus saliva not only helps in digestion of food but also convert into energy generating substances. Further, enzyme and their activity are very sensitive to temperature and pH. Even a slight variation in these two factors, can disturb the action of enzymes. In other words, digestion of food by salivary amylase is also effected by temperature and pH and can be verified experimentally. For example, hydrolysis of starch can be verified by testing it with iodine solution. Starch forms blue coloured complex with iodine. If no starch is present in a system it will not give blue colour with iodine. Update your Ennd Gafatwu SCRIBD Download any document, ad-free. ST CUE RecsRead without ads. Tete an eg J | aratus Required The requirements for experiment of chemistry project report Are as follow. 1. Test tubes 2. Test tube stand 3. One dropper 4. Beaker 5. Stop watch 6. Starch 7. Iodine solution 8. Thermometer 9. Dilute HCI solution 10. Dilute NaOH solution SCRIBD Download any document, ad-free. ST UE RecsRead without ads. Stee eet an Experiment 1 Aim.- To study the digestion of starch by saliva Procedure for Chemistry Experiment 1 is: 1. Collection of Saliva.- Rinse mouth thoroughly with cold water and ensure that it does not contain any food particles. Now take about 250ml of lukewarm water in the mouth and keep for about three minutes so that saliva mixes up well with it. Spit this into a beaker. Filter, if there is any suspended impurity clear filtrate is saliva solution and contains enzyme ptylin. 2. Preparation of starch solution.- Take about 0.5g of starch in 100ml beaker and add enough water to make a paste. Dilute the paste by adding 50ml water and boil for about 5 minutes. 3. Digestion of starch:- a. Take 5ml of the starch solution in a test tube. Add 2m of saliva solution into it. Mix the solution well by shaking the tube carefully and start a step watch. b. After one minute, take out two drops of the mixture solution from the test tube with the help of dropper and transfer it into another test tube containing about Iml of 1% iodine solution. Note the colour produced, if any. SCRIBD Download any document, ad-free. ST UE ReedRead without ads. Stee eer an d. Repeat this test after every one minute taking two drops of the mixture solution and fresh 1% iodine solution continue until the test shows no blue colour. e. Record the time and blue colour intensity. Observation Time Passed after 1 2 3 4 Mixing minute | minute | minute | minute Colour Intensity Deep Blue Light | No Blue Blue Blue Absence of blue colour on addition to iodine solution means absence of starch in the mixture solution. That is whole of the starch has got digested or hydrolysed. Conclusion Starch gets hydrolysed by salivary amylase ADVERTISING Download SCRIBD Download any document, ad-free. SUE ReedSEW cot ust Cornet Subscribe with a free trial Experiment 2 Aim.- To study the effect of temperature on the digestion of starch by saliva. Procedure for Chemistry Experiment 2 ts: . Take three test tubes and label these 1,2, and 3. Take 5m of the starch solution, 2ml of the saliva solution and 5m of water in each test tube. And shake the test tubes carefully. . Place test tube number 1 in water at room temperature, test tube number 2 in a beaker containing water at 50°C and test tube number 3 in boiling water. . After 5 minutes, observe the colour change on mixing two drops of the mixture of every tube with one ml of 1% iodine solution. Note the intensity of blue coloured form. Petes1- 1) Read without ads. Millions of documents at your Download iy tone Mee co § SCRIBD Download any document, ad-free. SUE RR UCLRead without ads. Stee eer un Observation Time passed after Intensity of blue colour mixing saliva Test tube 1 at olution with starch room Test tube 2 at 50°C | Test tube 3 i solution (in min) temperature boiling wate Light blue Blue Deep blue No blue colour Light blue Blue - Faint blue Blue - No blue colour Blue - - Blue - - Blue Conclusion Temperature affects the digestion of starch by saliva. Download mura SCRIBD Download any document, ad-free. SUE Rec |Read without ads. Stee eet an Experiment 3 Aim.- To study the effect of pH on the salivary digestion of starch. Procedure for Chemistry Experiment 1 is: . Take three test tubes and label these 1,2, and 3. 2. Add 5m of the starch solution, 2ml of the saliva solution in each test tube. 3. Now as 2ml of water in test tube number | 2ml of Dilute HCI in test tube number 2 and 2ml of Dilute NaOH solution in test tube number 3 and shake carefully. . Keep the three test tubes in water at room temperature for about 10 minutes. . Add 2 drops of the solution of each test tube with 1% iodine solution and observe the colour change. Observation Colour produced (in test Solution taken tube) with 1% iodine solution Starch + saliva + water No blue colour Starch + saliva +dil. HCI Blue colour Starch + saliva + dil. NaOH Blue colour Conclusion Hydrolysis of starch by the enzyme does not take place in the acidic or alkaline medium. ADVERTISING SCRIBD Download any document, ad-free. ST UE ReedRead without ads. OTe eet ar Precaution All apparatus should be clean and washed properly. Add equal drops of iodine in all the samples while testing for starch. . Temperature variation affects enzyme activity, so take the readings at a constant temperature for all the samples. Delay in sampling or the reaction time may affect the result. So, iodine drops must be added at fixed intervals in all samples. SCRIBD Download any document, ad-free. ST UE Rear3:33 9 ull > € Scribd guptaanuradha863, please verify your em... Secure your account by verifying your email address. Secure your account by verifying y... Bibliography Wikipedia-the free encyclopedia . hittp://www.google.com/ http://en.wikipedia.org Comprehensive Chemistry Chemistry NCERT Class XII" Dinesh chemistry Lhank youl! Clow. 2h A. SCRIBD Download any document, ad-free. STU Rec |