Biomolecules

Which vitamin deficiency causes rickets in children?

1. Vitamin A
2. Vitamin B12
3. Vitamin C
4. Vitamin D

Which of the following statements correctly distinguishes DNA from RNA?

1. DNA contains ribose sugar, whereas RNA contains deoxyribose sugar.
2. DNA contains uracil, whereas RNA contains thymine.
3. DNA is usually double-stranded, whereas RNA is generally single-stranded.
4. DNA contains peptide bonds, whereas RNA contains glycosidic bonds.

Hydrolysis of sucrose produces:

1. Glucose + Glucose
2. Glucose + Fructose
3. Fructose + Fructose
4. Glucose + Galactose

Which of the following amino acids is classified as an essential amino acid for humans?

1. Glycine
2. Alanine
3. Valine
4. Serine

Enzymes are generally:

1. Lipids
2. Proteins
3. Carbohydrates
4. Nucleic acids

Which of the following is the principal storage polysaccharide in animals?

1. Cellulose
2. Starch
3. Glycogen
4. Maltose

Which nitrogenous base is present in RNA but absent in DNA?

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

Protein denaturation refers to:

1. Breaking peptide bonds to form amino acids
2. Loss of biological activity due to destruction of secondary and tertiary structures
3. Conversion of proteins into carbohydrates
4. Formation of peptide bonds

Which of the following sugars gives a positive Tollens' test?

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

Which vitamin is also known as ascorbic acid?

1. Vitamin A
2. Vitamin C
3. Vitamin D
4. Vitamin K

Which of the following is a polysaccharide?

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

The linkage joining two amino acids in a protein is called:

1. Glycosidic bond
2. Hydrogen bond
3. Peptide bond
4. Phosphodiester bond

The product formed when glucose is reduced with hydrogen in the presence of nickel catalyst is:

1. Gluconic acid
2. Sorbitol
3. Fructose
4. Saccharic acid

Which of the following carbohydrates is a non-reducing sugar?

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