Define biodegradable and non-biodegradable and classify common items. Explain what an ecosystem is and draw a labeled diagram.

Let's solve the questions from Section D, Environment.

QUESTION 11:

11.1) Define the terms biodegradable and non-biodegradable.

• Biodegradable: These are materials that can be naturally broken down and decomposed by microorganisms (like bacteria and fungi) into simpler, harmless substances, eventually returning to the environment.
• Non-biodegradable: These are materials that cannot be broken down or decomposed by natural biological processes. They persist in the environment for very long periods, often causing pollution.

11.2) Arrange the following items under Biodegradable and Non-Biodegradable: Banana peels, cans, plastic, papers, bottles, dead plants, animal waste, metal scraps, groundnut peels.

Biodegradable	Non-Biodegradable
1. Banana peels	1. Cans
2. Papers	2. Plastic
3. Dead plants	3. Bottles
4. Animal waste	4. Metal scraps
5. Groundnut peels
6.

QUESTION 12:

12.1) What is an ecosystem?

An ecosystem is a community of living organisms (biotic components) interacting with each other and with their non-living physical environment (abiotic components) in a specific area. Energy flows and nutrients cycle within an ecosystem.

12.2) Draw a well labeled food chain of your choice, Four different categories of a food chain.

Here is an example of a food chain with four different categories (trophic levels):

$$\text{Grass (Producer)} \longrightarrow \text{Grasshopper (Primary Consumer)} \longrightarrow \text{Frog (Secondary Consumer)} \longrightarrow \text{Snake (Tertiary Consumer)}$$