Our Environment

Our Environment

Our Environment

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Question 1. Why are some substances biodegradable and some non-biodegradable ? 
Answer: Substances that are broken down by biological processes are said to be biodegradable. In our environment, many of the substances are broken easily by decomposers (bacteria and fungi) as they possess specific enzymes for such activity. However, there are other substances also which are not broken down in this manner and are known as non-biodegradable substances. Since these substances are not degraded by bacteria and fungi, so they persist for a long time. These non-biodegradable substances will be acted upon by physical processes like heat and pressure.
Question 2. Give any two ways in which biodegradable substances would affect the environment.
Answer:

1. They may produce foul smell during decomposition process.
2. They may produce some harmful gases such as ammonia, methane, carbon dioxide, etc., which can further-cause global warming.

Question 3. Give any two ways in which non-biodegradable substances would affect the environment.
Answer:

1. These inert substances simply persist in the environment. This means that these substances require land area for dumping.
2. Excess of fertilizers, pesticides and other chemicals changes soil chemistry and also affects aquatic life.
3. Most of these chemicals and heavy metal are easily absorbed by the organisms. This causes biological magnification.

OUR ENVIRONMENT