Hello,
In our class, we are doing a hypothetical digestion of starch by amylase lab. I do not know where to begin with this following information. If I add Benedict's solution (which I know will change color when the presence of sugar is noted).
After all of these tubes are submerged in boiling water with Benedict's what would happen and why?
Tube A: Starch + saliva treated with HCI(acid)
Tube B: Starch + saliva and water, treated in a boiling water bath
Tube C: Starch + saliva
Thanks for any insight!
Some thinking is involved here. Amylase is produced in saliva, and that breaks down long chain starches to simple sugars.
Amylase, an enzyme, is deactivated by stomach acid, and by heat.
http://en.wikipedia.org/wiki/Alpha-Amylase
To understand what would happen to the tubes when submerged in boiling water with Benedict's solution, let's break down each tube and discuss the reaction process involved.
Tube A: Starch + Saliva treated with HCI (acid)
In this tube, starch is mixed with saliva, and then HCI (hydrochloric acid) is added. HCI is an acid that helps in the breakdown of starch into simpler compounds. When this mixture is submerged in boiling water with Benedict's solution, no visible change will occur. Benedict's solution is used to test for the presence of reducing sugars, meaning sugars that can donate electrons and reduce other compounds. However, in this case, the starch has not been broken down into reducing sugars yet since HCI's main role is to create an acidic environment for the enzyme amylase to function optimally.
Tube B: Starch + Saliva and Water, treated in a boiling water bath
In this tube, starch is mixed with saliva and water. When submerged in boiling water with Benedict's solution, no visible change will occur. Similar to Tube A, the starch has not been broken down into reducing sugars. The presence of water does not significantly affect the reaction.
Tube C: Starch + Saliva
In this tube, starch is mixed with saliva but without any additional treatments. When submerged in boiling water with Benedict's solution, a visible change will occur. The Benedict's solution contains an alkaline copper sulfate solution, which turns from blue to green, yellow, orange, or brick-red in the presence of reducing sugars. Saliva contains an enzyme called amylase, which breaks down starch into reducing sugars like maltose. Therefore, the amylase in the saliva will gradually break down the starch into reducing sugars, resulting in a color change in the Benedict's solution.
It's important to note that the reaction process described above is a hypothetical digestion of starch by amylase. In a real lab setting, more precise procedures and measurements would be followed to ensure accurate results.