Which of the following is/are correct?
A. The various components of an ecosystem are independent.
B. Substances that cannot be broken down by biological processes, like plastics, are called biodegradable.
C. Disposable cups and plates are biodegradable substances.
D. It is better to use paper bags than polythene bags.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → D only
Biodegradable substances are those that bacteria and other decomposers can break down into simple harmless substances; non-biodegradable ones, such as plastics, cannot be broken down this way and stay in the environment for a very long time.
A. The various components of an ecosystem are independent. Incorrect. Producers, consumers, decomposers and the non-living parts depend on one another for food and for the cycling of materials, so they are interdependent.
B. Substances that cannot be broken down by biological processes, like plastics, are called biodegradable. Incorrect. Such substances are non-biodegradable.
C. Disposable cups and plates are biodegradable substances. Incorrect. Most disposable cups and plates are made of plastic, thermocol or plastic-coated paper, which decomposers cannot break down.
D. It is better to use paper bags than polythene bags. Correct. Paper is biodegradable, while polythene stays in the soil and water for years.