a. The household waste or rubbish produced in our day-to-day life is called garbage. For example, spoilt food, vegetable peels, leaves, wood, grass, paper, plastic, etc.
Garbage is classified into the following two types:
i. Biodegradable garbage - Garbage that can be decomposed naturally. Examples - vegetable peels, leaves, paper, etc.
ii. Non-Biodegradable garbage - Garbage that cannot be decomposed naturally. Examples - metal, plastics, etc.
b. Catalyst , Enzymes are biological molecules, usually proteins, that catalyze chemical reactions by lowering the activation energy required for the reaction to occur. Each enzyme is designed to catalyze a specific chemical reaction, and it does so by recognizing and binding to a specific substrate or group of substrates.