5. Which of the following sugars howe the same number of carbon as present in glucose?

1. Fructose

2. Erythrose

3. Ribulose

4. Ribose

When we homogenise any tissue in an acid, the acid-soluble pool represents

1. cytoplasm 

2. cell membrane

3. nucleus

4. mitochondria

The most abundant chemical in living organisms could be

1.  protein 

2.  water

3.  sugar

4.  nucleic acid

A homopolymer has only one type of building block called monomer repeated ‘n’ number of times. A heteropolymer has more than one type of monomer. Proteins are heteropolymers usually made of

1.  20 types of monomers

2.  40 types of monomers

3.  30 types of monomers

4.  only one type of monomer

Proteins perform many physiological functions. For example, some functions as enzymes. One of the following represents an additional function that some proteins discharge

1.  Antibiotics

2.  Pigment conferring colour to skin

3.  Pigments making coloursof flowers

4.  Hormones

Glycogen is a homopolymer made of

1.  glucose units

2.  galactose units

3.  ribose units

4.  amino acids

The number of ‘ends’ in a glycogen molecule would be

1.  Equal to the number of branches plus one

2.  Equal to the number of branch points

3.  One

4.  Two, one on the left side and another on the right side

The primary structure of a protein molecule has

1.  two ends

2.  one end

3.  three ends

4.  no ends

Enzymes are biocatalysts. They catalyze biochemical reactions. In general, they reduce the activation energy of reactions. Many physicochemical processes are enzyme-mediated. Which of the following reactions is not enzyme-mediated in the biological system?

1.  Dissolving CO₂ in water

2.  Untwining the two strands of DNA

3.  Hydrolysis of sucrose

4.  Formation of peptide bond

An amino acid under certain conditions has both positive and negative charges simultaneously in the same molecule. Such a form of amino acid is called

1. acidic form

2. basic form

3. aromatic form

4. zwitterionic form