Biochemistry-I MCQs | BIO202 MCQs | Set 7 | Query Point Official
Biochemistry-I MCQs | BIO202 MCQs | Set 7
MCQs (Multiple Choice Questions)
1) Choose a suger out of the following that is non reactive to Seliwanoff reagent?
a) Sucrose
b) Fructose
c) Inulin
d) Ribose
Correct Answer:
The correct answer is 'd'.
Explanation:
Seliwanoff's reagent is used to distinguish between ketose and aldose sugars. Ketose sugars react with Seliwanoff's reagent to produce a cherry-red color, while aldose sugars do not react.
______________________________
2) Choose a keto triose:
a) Glyceraldehyde
b) Dihydroxyacetone
c) Erythrose
d) Arabinose
Correct Answer:
The correct answer is 'b'.
Explanation:
______________________________
3) A pentose sugar present in the heart muscle is:
b) Xylulose
c) Lyxose
d) Aldose
Correct Answer:
The correct answer is 'c'.
Explanation:
Lyxose is a pentose sugar that can be found in various tissues, including the heart muscle. It is an aldose, which means it is a sugar with an aldehyde functional group.
______________________________
4) d-Glucose and I-Glucose are:
a) Stereo isomers
b) Anomers
c) Keto-Aldose
d) Optical isomers
Correct Answer:
The correct answer is 'd'.
Explanation:
d-Glucose and l-Glucose are optical isomers, also known as enantiomers. They have the same chemical formula but differ in their three-dimensional spatial arrangement, making them non-superimposable mirror images of each other. Stereoisomers are a broader category that includes enantiomers, diastereomers, and others. Anomers refer to specific types of stereoisomers related to the cyclic structure of sugars.
______________________________
5) All the following tests are positive for Lactose except ________.
a) Benedict
b) Barfoed
c) Molisch
d) Osazone
Correct Answer:
The correct answer is 'd'.
Explanation:
The osazone test is used to identify monosaccharides, such as glucose and fructose. Lactose is a disaccharide made up of glucose and galactose. Therefore, lactose will not give a positive osazone test.
______________________________
6) Glucose can have _____ isomers due to the presence of 4 asymmetric carbon atoms.
a) 4
b) 2
c) 12
d) 16
Correct Answer:
The correct answer is 'd'.
Explanation:
Glucose can have 16 stereoisomers due to the presence of 4 asymmetric (chiral) carbon atoms. Each chiral carbon can have two possible configurations (R and S), and when you multiply the possibilities for all four chiral carbons, you get a total of `2^4` = 16 stereoisomers.
______________________________
7) Fructose and Ribulose are:
a) Epimers
b) Anomers
c) Ketoses
d) Ketose-Aldose isomers
Correct Answer:
The correct answer is 'c'.
Explanation:
Ketoses are monosaccharides that have a ketone functional group. Fructose and ribulose are both ketoses.
______________________________
8) The compounds having same structural formula but differing in configuration around one carbon atom are called:
a) Optical isomers
b) Anomers
c) Stereo isomers
d) Epimers
Correct Answer:
The correct answer is 'd'.
Explanation:
The compounds having the same structural formula but differing in configuration around one carbon atom are called epimers. Epimers are a type of stereoisomer and are characterized by their differences at a single chiral center. Anomers are a specific type of epimer related to the cyclic structure of sugars. Stereoisomers is a broader term that encompasses various types of isomers that differ in their spatial arrangement. Optical isomers (enantiomers) are a subtype of stereoisomers.
______________________________
9) What does the following equation represent?
`alpha`-D Glucose + 112o`\rightarrow`+52.5o`\rightarrow`+19o`\beta` - D glucose
a) Stereois omerism
b) Optical isomerism
c) Mutarotion
d) Epimerization
Correct Answer:
The correct answer is 'c'.
Explanation:
The equation represents mutarotation, which is a phenomenon in which the specific rotation (observed optical rotation) of an optically active compound changes over time when dissolved in a solvent. In this case, it's referring to the mutarotation of α-D-glucose to β-D-glucose, where the specific rotation values change as the glucose solution shifts between the α and β forms. Mutarotation is a characteristic of compounds that can exist in different anomeric forms (such as α and β) and is a type of optical isomerism.
______________________________
10) The carbohydrate of honey is
a) Fucose
b) Maltose
c) Lactose
d) Fructose
Correct Answer:
The correct answer is 'd'.
Explanation:
Fructose is a monosaccharide, which means that it is the simplest form of carbohydrate. It is a ketose sugar, which means that it has a ketone functional group. Fructose is one of the sweetest sugars, and it is responsible for the sweetness of honey.
______________________________
Related Posts
- Biochemistry-I MCQs | BIO202 Set 1
- Biochemistry-I MCQs | BIO202 Set 2
- Biochemistry-I MCQs | BIO202 Set 3
- Biochemistry-I MCQs | BIO202 Set 4
- Biochemistry-I MCQs | BIO202 Set 5
Frequently Asked Questions (FAQs)
What is the Seliwanoff test used for?
Seliwanoff’s reagent distinguishes ketoses from aldoses because ketoses react quickly producing a red color while aldoses do not.
What are epimers?
Epimers are sugars that differ only in configuration at one specific carbon atom.
What is mutarotation?
Mutarotation is the change in optical rotation as a sugar solution shifts between α and β anomeric forms.
What type of sugar is fructose?
Fructose is a ketose-type monosaccharide found in honey and many fruits.
How many stereoisomers can glucose have?
With four chiral centers, glucose can exist as 16 stereoisomers.
Related Topics
For more Introduction to BIOCHEMISTRY I topics, visit BIOLOGY Notes & MCQs.
Query Point Official – Smart Notes for Exams & Conceptual Learning
No comments