Previous Year Question

A Biodegradable material is one that can be broken down by bacteria, fungi and other microorganisms through natural biological processes into simpler substances.

Wool is a natural animal fibre. Its principal structural component is the Keratin protein. Keratin can gradually be broken down by certain microorganisms and their enzymes, making wool a biodegradable material.

Wool can therefore undergo natural decomposition, although the rate of decomposition depends on conditions such as moisture, temperature, microorganisms and processing.

Plastic cups are generally made from petroleum-derived synthetic polymers. Conventional plastics are not readily degraded by microorganisms and may persist in the environment for long periods.

Aluminium foil is a metallic material. It may undergo corrosion or chemical transformation, but it is not considered biodegradable in the sense of microbial biological decomposition.

A Glass bottle is primarily an inorganic silicate material. It may physically break into smaller pieces, but it does not undergo microbial biodegradation.