Practice on Biomolecules

Start practice on biomolecules

1. Carbohydrate

1. Which carbohydrate is used in silvering of mirrors ?

1. Sucrose
2.  Starch
3. Glucose
4. fructose

     

ans :c

2. Sucrose on hydrolysis gives:

1. glucose and galactose
2.  maltose and galactose
3. glucose and fructose
4. none of these

     

ans :c

3. Animal starch is the name given for:

1. glycogens
2.  lactogens
3. cellulose
4. none of these

     

ans :a

4. Biuret test is not given by:

1. proteins
2.  urea
3. polypeptide
4. carbohydrates

     

ans :d

5. Cellulose is a:

1. monosaccharide
2.  disaccharide 
3. polysaccharide
4. none of these

     

ans :c

6.  Hydrolysis of sucrose is called:

1. saponification
2.  hydration
3. inversion
4. esterification

     

ans :c

7. Common table sugar is more formally described as:

1. glucose
2.   lactose
3. maltose
4. sucrose

     

ans :d

8 .Which of the following statements is not true?

1. Pheromones are secreted outside the body by the insects
2.  Aspirin in analgesic and antipyretic
3. Sucrose is a disaccharide commonly known as aspartame
4. The DNA assists in the synthesis of RNA molecules

     

ans :c

9. Which does not contain carbohydrate?

1. Cellulose
2.  Wax
3. Starch
4. Wheat flour

     

ans :b

10. .Lactose has the same molecular formula as:

1.  glucose
2.  maltose
3. laevulose
4.  galactose

     

ans :b

11. The two forms of D-glucopyranose obtained from solution of D-glucose are known as:

1. anomers
2.  epimers
3. enantiomers
4. geometrical isomers

     

ans :a

12. Dihydroxy acetone(CH2OH.CO-CH2OH)has the general formula of carbohydrate but not included in this class because:

1.  it does not contain polyhydroxy gp.
2. it does not contain aldehyde gp.
3. it is not optically active
4.  all of the above

     

ans :c

13. Dextrin(C6H10O5)n are used in:

1. making adhesive
2.  confectionary
3. sizing paper
4. all of these

     

ans :d

14. The sugar present in honey is:

1.  sucrose
2.  glucose
3.  fructose
4. maltose

     

ans :c

15. A solution of D-glucose in water rotates the plane polarized light:

1.  to the right
2.  to the left
3.  to either side
4. none of these

     

ans :a

16. Glucose and fructose can be distinguished by:

1. Lucas test
2. Ninhydrin test
3. Benedict reagent test
4. All of these

     

ans :c

17. Gums are:

1. Polysaccharides of more than one type of monosacharides
2.   used as thickening agent
3. used for improvement of texture in food industry
4. all of the above

     

ans :d

18. The intermediate compound in the conversion of starch to glucose is:

1. lactose
2.  maltose
3.  fructose 
4.  sucrose

     

ans :b

19. Which statement about ribose is incorrect?

1. A polyhydroxy compound
2.  An aldehyde sugar
3. Has six carbon atoms
4. Exhibits optical activity

     

ans :c

20. Which of the following enzymes is used to convert starch to alcohol ?

1. Maltose,diastase
2.  Invertase,zymase
3. Diatase,maltase,zymase
4. Invertase,diastase,zymase

     

ans :c

21.  Starch is changed into disaccharides in the presence of:

1.  diastase
2.   maltase
3. lactase
4. zymase

     

ans :a

22. Aqueous solution of carbohydrate with 2 drops of alcoholic solution of o-naphthol and H2SO4 gives a ring at the junction.The color of the ring is:

1. yellow
2.  green
3. violet
4. red

     

ans :c

23. Which of the following gives reddish brown precipitate with dilute solution of resorcinol in dilute HCI?

1. Glucose
2.  Fructose
3. Lactose
4. Maltose

     

ans :b

24. Acetone may be obtained from starch by the action of:

1. acid
2.  bacteria
3. oxidizing agent
4. none of these

     

ans :b

25 .Glucose on reduction with Na/Hg and water gives:

1. sorbitol
2.  fructose
3. saccharic acid
4. gluconic acid

     

ans :a

26. The charring product formed when C6H1206is heated with conc.H2SO4 is due to:

1. oxidation
2. reduction
3. dehydration
4. dehydrogenation

     

ans :c

27. .Epimers are pair of diastereoisomeric aldoses which differ only in configuration at position;

1. C5
2. C2
3. C4
4. C3

     

ans :b

28. When glucose is heated with nitric acid,the product is:

1. gluconic acid
2. glucaric acid
3. glycolic acid
4. oxalic acid

     

ans :b

29. The polysaccharide used in the manufacture of paper is:

1. cellulose 
2. starch
3. glucose
4. sucrose

     

ans :a

30. Complete hydrolysis of cellulose gives:

1. D-glucose
2. L-glucose
3. D-fructose
4. D-ribose

     

ans :a

31. When sucrose is heated with concentrated nitric acid,the product is:

1. saccharic acid
2.  oxalic acid
3. formic acid
4. invert sugar

     

ans :b

32. The change in optical rotation with ime of freshly prepared solutions of sugar is known as:

1. specific rotation
2.  inversion
3. rotatory motion
4. mutarotation

   

ans :b

33. To become a carbohydrate,a compound must contain at least:

1. 6 carbons
2. 3 carbons
3. 4 carbons
4. 2 carbons

     

ans :b

2. Proteins

1. A certain compound gives negative test with ninhydrin and positive test with Benedict's solution,the compound

is:

1. a protein
2. a lipid
3. a monosaccharide
4. an amino acid

     

ans :c

2. Which one of the following metal ions is essential inside the cell for the metabolism of glucose/synthesis of

proteins?

1.  Na+
2.   K+
3. Mg2+
4. Ca2+

     

ans :c

3. Which of the following amino acids is not optically active?

1. Lysine
2. Tyrosine
3. Glycine
4. Alanine

     

ans :c

4.Lysine is least soluble in water in the pH range:

1. 3 to 4
2. 5 to 6
3. 6 to 7
4. 8 to 9

     

ans :c

5. Which of the following is a heterocyclic amino acid?

1. Tryptophan
2.  Phenylalanine
3. Glycine
4. Alanine

     

ans :a

6. The pKa,and pKaof an amino acid are 2.3 and 9.7 respectively.The isoelectric point of the amino acid is:

1. 6.0
2. 3.7
3. 12.0
4.  7.4

     

ans :a

7. Lysine is least soluble in water in the pH range:

1. 3 to 4
2. 5 to 6
3. 6 to 7
4. 8 to 9

     

ans :d

8. A nanopeptide contains-peptide linkages.

1. 10
2.  8
3. 9
4. 18

     

ans :b

9. Which one of the given proteins transports oxygen in the blood stream?

1. Myoglobin
2.  Insulin
3. Albumin
4. Hemoglobin

     

ans :b

3. Vitamins, Hormones and Nucleic Acid

1. Vitamin C is:

1.  ascorbic acid
2.  lactic acid
3. citric acid
4. paracetamol

     

ans :a

2. Which of the following bases is not present in DNA?

1. Cytosin
2.  Guanine
3. Uracil
4. Adenine

     

ans :c

3. Which of the following is not a fat soluble vitamin?

1. Vitamin A
2. Vitamin K
3. Folic acid
4. Vitamin E

     

ans :c

4. The segment of DNA which acts as the instrumental manual for the synthesis of the protein is:

1. ribose
2.  gene
3. nucleoside
4. nucleotide

     

ans :b

5. DNA multiplication is called

1. translation
2.   transduction
3. replication
4.  transcription

     

ans :c

6. The pair in which both the species have iron is

1. nitrogenase,cytochromes
2.  carboxypeptidase,hemoglobin
3. hemocyanin,nitrogenase
4. hemoglobin,cytochromes

     

ans :d

7. Artificial sweetener used in soft drinks is:

1. glucose
2. fructose
3. cellulose
4. aspartame

     

ans :d

8. Purity of butter is determined in terms of:

1. saponification value
2.  iodine value
3. acetyl value
4. Reichert-Meissl value

     

ans :d

9. The number of milligram of KOH required to neutralize 1g of the oil or fat is called:

1. saponification value
2.  iodine value
3. acetyl value
4. acid value

     

ans :a

10. Hydrolysis of fats and oils in the body produces:

1. a fatty acid
2.  carbon dioxide
3. a lipase
4.  an ester

     

ans :a

11. Which amino acid has no asymmetric carbon?

1. Histidine
2.  Threonine
3. 𝝰-alanine
4. Glycine

   

ans :d

12. Vitamin B,is chemically known as:

1. ascorbic acid
2.  riboflavin
3. pyridoxine
4.  thiamine

     

ans :d

13. The hormone that helps in conversion of glucose to glycogen is:

1.  cortisone
2.  bile salt
3. adrenaline
4.  insulin

     

ans :d

14. DNA and RNA are chiral molecule due to the presence of:

1. chiral bases
2.  phosphate ester unit
3.  D-sugar component
4. L-sugar component

     

ans :c

15. The segment of DNA which acts as the instrumental manual for the synthesis of the protein is:

1. nucleoside
2.  nucleotide
3.  ribose
4. gene

     

ans :d

4. Problem based on Mixed concept

1. Which of the following factors has the least influence on the secondary and tertiary structure of proteins?

1. The achiral nature of glycine units
2.  Steric hindrance of bulky side chains on the peptide backbone
3. Hydrogen bonding of C=O to N-H groups located near other space
4. Conformational restriction imposed by praline units

     

ans :a

2.D-mannose is epimeric with D-glucose at C2.Which of the following structures represents 𝞫-D-mannopyranose?

     

ans :c

3.  The following Carbohydrate is :

1. a ketohexose
2.  an aldohexose
3. an 𝛼-fructose
4. an 𝛼-pyranose

     

ans :b

4. Which product will be formed in the following reaction

     

ans :a

5. Which of the following aldohexose given the same osazone derivative ?

1.  I and IV
2.  I and III
3. II and III
4.  III and IV

     

ans :c

6.

The final product X is :

1. fructose
2.  mannose
3. aldoheptose
4. aldopentose

     

ans :c

7. The correct structure of the dipeptyl gly-ala is

     

ans :c