Answers :

1. Any substance that cannot be decomposed by the microorganism in nature into its monomers and causes harm to the environment is called a non - biodegradable substance . Plastic is a polymer that cannot be decomposed by microorganism and remains unaffected even for the period of MILLION of YEARS . Hence , these are termed non - biodegradable .

2. Plastic should be recycled rather than incinerated ( put down to ashes in incineration chambers) or burried inside soil because when burned plastic releases toxic gases and carbon DIOXIDE which causes global warming . Burying plastics will lead to increased LANDFILLING repeatedly . Thus they should be recycled into another usable form for AVOIDING any damage to the environment.

3. Plastics are non - biodegradable substance. When buried inside the soil , they do not get decomposed for over a span of millions of years causing soil pollution . They also choke the water bodies causing water pollution . Plastics are also a main source of air pollution because when burned , these release toxic gases into the environment .

4. A thermoplastic is a kind of plastic that can be molded repeatedly to another usable form whereas a thermosetting plastic is the one that once used cannot be molded again .