BIOLOGY
PREPARATION OF GLUCOSE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Glucose
|
|
|
Starch
|
|
|
Both of the above
|
|
|
None of the above
|
Detailed explanation-1: -Amylopectin from normal potato starch has a double-helix conformation, which does not readily dissolve in cold water [7].
Detailed explanation-2: -Starches are insoluble in neutral water at room temperature. However, if they are heated beyond the boiling point of water in a closed container, they eventually dissolve.
Detailed explanation-3: -Water insoluble component of starch is amylopectin. Water soluble component of starch is amylose.
Detailed explanation-4: -The amylose is readily soluble in cold water in a matter of seconds.
Detailed explanation-5: -When ethanol is added, which is less polar than water, it lowers the solubility and potential hydrogen bonds of the starch, because the water is more attracted to the alcohol than the starch, the starch is dehydrated by the alcohol and precipitates.