Quiz 2
1. A biologically important chemical reaction that breaks chemical bonds by
addition of water and release of high energy called Hydrolysis.
2. What does Benedict’s test detect? Æ Reducing Sugar.
3. Iodine bind to Starch and change the color from yellow to dark bluish.
4. The deoxyribose is a five-carbon sugar that is a part of DNA. Do you think the
Benedict’s test can detect the presence of *pure doxyribose? (* The deoxyribose
is not the part of DNA, but by itself as single molecule!) Explain your answer.
According to the figure, the deoxyribose is a reducing sugar contains free aldehyde and ketone
group. The number of carbons does not matter for reducing sugars. Most monosaccharides
are reducing sugars. Thus, the correct answer is “Yes, the Benedict reagent would detect the
pure deoxyribose.
5. The Biuret Reagent detects specific chemical bond. What is the name of the
chemical bond? Æ Peptide Bond
6. The grease spot test is used to detect presence of Lipids.
7. The Dische diphenylamine is used to detect what biological molecule?
Æ DNA or Deoxyribose
If you put RNA and/ or Nucleic acid, you were wrong. Read the text again.
8. Where are you supposed to discard the Dische diphenylamine?
Æ Special Waste bottle/ container
9. You are asked to design an experiment to detect the presence of Deadly
microbious, a deadly microorganism from a patient’s blood. What would you use
for a positive control? A negative control?
a. Positive control: Deadly microbious
b. Negative control: Water, solution without the microorganism
Although the positive control must contains the Deadly microbious, any blood samples
contain the microorganism cannot be the control. Whoever got the microorganism are patients, and
patients’ blood cannot be the control. Any blood should not be used for controls. However, if ethics
accept clean blood for the negative control, then it could be used as a control (… yet still not
realistic).
10. What is a major theme of today’s exercise? Æ Enzyme
Bonus: Name one of factors that will change enzyme activities.
Æ Temperature, pH, Inhibitor, and other chemical substances.