Tag: carbohydrate and its test

Quizzes (0) Questions (100)

Questions Related to carbohydrate and its test

Multiple choice biology biological molecules energy giving food carbohydrate and its test food and it's constituents

A reagent added to a sample shows change of colour from green to yellow. It is due to presence of reducing sugar. The test is

  1. Elisa test for detecting AIDS

  2. Benedict's test for detecting glucosuria

  3. Fehling's test for detecting hyperglycemia

  4. Ninhydrin test for detecting glucosidic linkage
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Benedict's test can be used to test reducing sugar that is glucose in urine. Glucose in urine is called glucosuria and it turns yellow in colour when benedict's test applied it shows that glucose is present in urine.
So the correct answer is B.
Multiple choice biology biological molecules energy giving food carbohydrate and its test food and it's constituents

Starch changes colour and turns blue-black in ............ solution.

  1. Salt

  2. Eosin

  3. Iodine

  4. Dilute HCl
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Iodine present in the aqueous Potassium iodide solution gets entangled in the starch and forms starch Iodide complex. Hence starch turns blue-black or purple-black in colour.

So, the correct answer is option C.

Multiple choice biology biological molecules energy giving food carbohydrate and its test food and it's constituents

A leaf is boiled in alcohol before using iodine for a starch test in order to

  1. dissolve starch

  2. dissolve chlorophyll

  3. soften the leaf

  4. make it react with iodine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Boiling a leaf in alcohol removes chlorophyll, which otherwise masks the color change when testing for starch with iodine. Once the chlorophyll is dissolved, the leaf becomes white or pale, making the blue-black iodine color change clearly visible.

Multiple choice biology biological molecules energy giving food carbohydrate and its test food and it's constituents

The post prandial glucose can be measured 

  1. Empty stomach

  2. Any time

  3. 2 hours after lunch / dinner

  4. Early in the morning
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Blood glucose levels are maintained by hormones, such as insulin and glucagon. A postprandial glucose test is a blood glucose test that determines the amount of glucose in the blood after a meal. Normally, blood glucose levels increase slightly after eating. This increase causes the pancreas to release insulin. A postprandial blood glucose test measures blood glucose exactly 2 hours after eating a meal. By this point, blood sugar has usually gone back down in healthy people, but it may still be elevated in people with diabetes.

Multiple choice biology biological molecules energy giving food carbohydrate and its test food and it's constituents

For the test of sugars _______ is used.

  1. Fehling's solution

  2. Benedict's solution

  3. Iodine solution

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A little glucose is added to a blue green chemical called as Fehling's solution in a test tube for test of glucose.

Benedict's solution can be used for detecting reducing sugars.
Iodine solution also called as Lugol's reagent is used for detection starch and complex sugars. So, the correct answer is option D. 

Multiple choice biology biological molecules energy giving food carbohydrate and its test food and it's constituents

How many NADH molecules are produced during the complete breakdown of one molecules of glucose?

  1. 5

  2. 10

  3. 30

  4. 6
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During the complete breakdown of one glucose molecule via glycolysis, the link reaction, and the Krebs cycle, a total of 10 NADH molecules are produced (2 in glycolysis, 2 in the link reaction, and 6 in the Krebs cycle). In addition, 2 FADH2 molecules are also produced.