<u>Answer</u>:- A material is considered biodegradable if it can be broken down by biological processes.
<u>Explanation</u>:-
1. There are many living organisms such as bacteria, fungi and other microbes that feed on organic matter and convert them into simpler forms.
2. Due to the enzymes released by such microbes, all the materials such as food refuse, tree leaves, grasses etc. are considered to be <em>biodegradable </em>as they are capable of being broken down by them.
3. The materials that cannot be broken down by such living organisms are considered to be <em>non biodegradable</em>.
4. The non biodegradable substance produce a problem in the environment as they persist for a long period of time and also form a major source of pollution for soil and water. Further, they may also cause harm to other living organisms present in the environment.
5. Example of a non biodegradable substance is plastic.
