Many organic substances are negatively charged e.g., acetic acid, while others are positively charged e.g., ammonium ion. An amino acid under certain conditions would have both positive and negative charges simultaneously in the same molecule. Such a form of amino acid is called

1.	Positively charged form	2.	Negatively charged form
3.	Neutral form	4.	Zwitter ionic form

Sugars are technically called carbohydrates, referring to the fact that their formulae are only multiples of C(H₂O). Hexose therefore has six carbons, twelve hydrogen and six oxygen atoms. Glucose is a hexose. Choose from among the following another hexose.

When you take cells or tissue and grind them with an acid in a mortar and pestle, all the small biomolecules dissolve in the acid. Proteins, polysaccharides and nucleic acids are insoluble in mineral acid and get precipitated. The acid soluble compounds include amino acids, nucleosides, small sugars etc. When one adds a phosphate group to a nucleoside, one gets another acid soluble biomolecule called

When we homogenize any tissues in an acid the acid soluble pool represents

The most abundant chemical in living organisms could be
1. Protein
2. Water
3. Sugar
4. Nucleic acid

A homopolymer has only one building block called monomer repeated ‘n’ number of times. A heteropolymer has more than one type of monomers. Proteins are heteropolymers made of amino acids. While a nucleic acid-like DNA or RNA is made of only 4 types of nucleotide monomers, proteins are made up of
1. 20 types of monomers
2. 40 types of monomers
3. 3 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. Pigment making colours of 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
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

A pure protein should normally have