Biomolecules

Topics in this chapter

• Carbohydrate Structure
• Carbohydrate Reactions
• Amino Acids And Proteins
• Nucleic Acids
• Lipids, Vitamins And Hormones

Cheat sheet

Practice questions

1. Question 1Q-80AE17

   Which of the following statements is incorrect regarding peptide linkages in proteins?

   1. A.A peptide bond is formed by the elimination of a water molecule between the carboxyl group of one amino acid and the amino group of another.
   2. B.The peptide bond has a partial double bond character due to resonance.
   3. C.Rotation around the peptide carbon-nitrogen bond is relatively free and unrestricted.
   4. D.In a peptide bond, the carbonyl oxygen and the amide hydrogen are mostly in the trans configuration.
   See the answer and solution
2. Question 2Q-9B6DDF

   Which of the following bases is present in RNA but completely absent in DNA?

   1. A.Adenine
   2. B.Thymine
   3. C.Uracil
   4. D.Cytosine
   See the answer and solution
3. Question 3Q-0606E6

   Glucose on reaction with excess of phenylhydrazine gives:

   1. A.Glucosazone
   2. B.Phenylgluconate
   3. C.Sorbitol
   4. D.Gluconic acid
   See the answer and solution
4. Question 4Q-5AC516

   Which of the following vitamins is water-soluble and cannot be stored in our body?

   1. A.Vitamin A
   2. B.Vitamin D
   3. C.Vitamin C
   4. D.Vitamin K
   See the answer and solution
5. Question 5Q-849F28

   Denaturation of proteins leads to the loss of biological activity by disrupting which of the following structures?

   1. A.Primary structure only
   2. B.Primary and secondary structures
   3. C.Secondary and tertiary structures
   4. D.Only peptide bonds
   See the answer and solution