Table of ContentsMaterials:Discussion:Conclusion:The purpose of this laboratory is to determine the optimal conditions for digestion in the stomach. This lab will focus on chemical digestion by gastric fluid, using pepsin and egg along with an acid, base, or neutral solution to model conditions in the stomach. Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”? Get the original essay Materials: - 1 pH paper tube - 16 ml of 1% pepsin - 4 ml of 0.2 hydrochloric acid % -4 ml of 1% sodium bicarbonate -4 ml of distilled water -4 test tube caps -4 test tubes -8 grams of hard-boiled egg white -Scale (to measure the egg) -Graduated cylinder -Pencil ( to mark test tubes) -Scalpel (to cut pieces of egg) -Test tube rackDiscussion:As shown in Figure 1, each test tube produced different results. Some had a cloudy solution, others had condensation on the side of the test tube, and still others caused the egg to float in the solution. Each test tube showed at least trace dissolution of the egg, likely due to the time spent in the solution. However, while the egg dissolved very slightly in test tubes A, C, and D, it was by far the egg that dissolved the most in test tube B. Stomach fluids are made up of mucus, hydrochloric acid and pepsinogen (Holt, Rinehart, Winston, 2009, page 988). Pepsinogen is inactive until hydrochloric acid converts it to pepsin, a digestive enzyme (Holt, Rinehart, Winston, 2009, page 988). Additionally, pepsin must have a low pH, around 2, for digestion to occur most efficiently, and this is why the egg in test tube B dissolves the most ("Experiment 10-Enzymes", 2012). The egg would partially dissolve in water, as it would in the stomach, but the rate of dissolution is much slower without pepsin and it is inactive without the hydrochloric acid that converts it to pepsinogen. This is why test tubes A, C and D saw their egg dissolve slightly. Sodium bicarbonate is a base, and so test tube A is too far from the optimal pH of 2 for the egg to be effectively dissolved by pepsin. The distilled water and control group are neutral, and test tubes D and C, respectively, are therefore too far from the optimal pH of 2 for the egg to be effectively dissolved by pepsin. Hydrochloric acid is an acid and so test tube B is close enough to the optimal pH of 2 for the egg to be effectively dissolved by the pepsin. The group's hypothesis was: If distilled water is added to a solution of pepsin and egg, it will digest the egg more efficiently than the acid (hydrochloric acid) or base (sodium bicarbonate). , because food must be broken down by hydrolysis in order to digest it. The data rejected the hypothesis. The group did not realize that the enzyme could carry out hydrolysis on its own, and it was not until the end of the laboratory that optimal conditions for pepsin were achieved. Then students understood why hydrochloric acid dissolved the egg most effectively, and not distilled water. Biuret's solution is used to test for the presence of proteins. The reagent is blue at first, but turns purple if it detects the presence of peptide bonds, the chemical bonds that attach amino acids to each other (Bank, n.d.). Even though the amount of protein digested in the body is greater than that contained in a test tube, the surface area of ​​the organs involved in digestion and absorption (e.g. the villi of the small intestine) is proportionally much larger . He..