CBSE Class 10 Science 2023 · Paper 31/5/3 · Question 25

Difference: biodegradable substances are broken down by biological processes, that is by micro-organisms such as bacteria and fungi, into simpler, harmless substances (for example vegetable peels, paper, cotton cloth). Non-biodegradable substances are not broken down by biological processes, so they persist in the environment for a long time and may harm the ecosystem (for example plastics, glass, DDT). Two methods of safe disposal of biodegradable domestic waste: (i) Composting: the kitchen and garden waste is put in a pit and covered with soil, and micro-organisms decompose it into manure (compost). (ii) Vermicomposting: the waste is fed to earthworms in a pit or bin, which turn it into vermicompost, a rich manure. (Producing biogas from the waste in a biogas plant is also a safe method.)