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FHSB 1214
BIOLOGY 1
FOUNDATION IN SCIENCE

Name| LEE KEH JIE (1302255)|
Partner’s Name| SHERMAN TAN WEI MING (1302523) CHONG DICK BAN (1302376)| Practical Group| Stream P- Group 3|
Date of lab class| 17/06/2013|
Program| Foundation in Science|
Unit code| FHSB1214|
Unit description| Biology I|
Year and trimester of study| 2013, Trimester 1|
Title of lab report|  Practical 3: Identification of Action of Saliva and 3M Hydrochloric Acid in Two Carbohydrates Solution| Lecturer’s name| MS. BONG SM|

Title of lab report:
Practical 3: Identification of Action of Saliva and 3M Hydrochloric Acid in Two Carbohydrates Solution. Objective:
To determine the type of carbohydrates.
Results:
Table 1:
| Observations| Conclusions|
Solution A| Benedict’s test: (Positive results), Pale blue colour solution changes to orange colour solution.Iodine test: (Negative results), Orange colour solution remains the same. | -Solution A is a reducing sugar. --Starch is absent in solution A.| Solution B| Benedict’s test: (Negative results), Blue colour solution remains the same.Iodine test: (Positive results), Orange colour solution changes to dark purple colour solution.| -Solution B is a non-reducing sugar. -Starch is present in solution B.|

Table 2:
Tube| Contents| Temp(°C)| Benedict’s Test—Colour Observation| | | | After 5th min (from tubes 1 – 4 into 1’ – 4’)| After 35th min (from tubes 1 – 4 into 1’ – 4’)| 1| 10 ml solution B 1 ml saliva| 37| (Positive results, less precipitate than 35th min), Colourless solution changes to dark green colour solution.| (Positive results), Dark green colour solution changes to blue colour solution.| 2| 10 ml solution B 1 ml 3 M HCl| 37| (Negative results), Colourless solution changes to blue colour solution.| (Negative results), Blue colour solution remains the same. | 3| 10 ml solution B 1 ml 3 M HCl| 95| (Positive results, less precipitate than 35th min), Colourless solution changes to blue colour solution.| (Positive results), Blue colour solution remains the same. | 4| 10 ml solution B 1 ml saliva| 95| (Negative results), Colourless solution changes to greenish- blue solution.| (Negative results), Greenish blue solution remains the same.|

Discussion:
Enzyme involved in the experiment is salivary amylase.
Salivary amylase is an enzyme that catalyses the breakdown of starch into sugars. Amylase is present in human saliva. The amylase attacks the second linkage from the non-reducing terminals (i.e. C4 end) of the straight segment, resulting in the splitting off of two glucose units at a time. The product is a disaccharide called maltose. The bond breakage is thus more extensive in saccharify-ing enzymes than in liquefying enzymes. The starch chains are literally chopped into small bits and pieces. Finally, the amyloglucosidase (also called glucoamylase) component of an amylase preparation selectively attacks the last bond on the nonreducing terminals. The type to be used in this experiment can act on both the alpha-1,4 and the alpha-1,6 glucosidic linkages at a relative rate of 1:20, resulting in the splitting off of simple glucose units into the solution. Fungal amylase and amyloglucosidase may be used together to convert starch to simple sugars. The practical applications of this type of enzyme mixture include the production of corn syrup and the conversion of cereal mashes to sugars in brewing. When hydrochloric acid puts H+ in Solution B. The lone pairs of the oxygen in the C-O-C bond will attack this H+. Now oxygen is bound to three things; it is unstable. Because acid allows this destabilization to occur, it lets hydrolysis of the bond occur. For every enzyme,there are optimal conditions under which it is most effective .Temperature affects molecular motion.An enzyme’s optimal temperature produces the highest rate of contact between reactants and enzyme’s active site.Most...
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