Chapter: 18. The Environment
Section A: Multiple Choice Questions (MCQs)
b) Reduce, Reuse, Recycle Section B: Fill in the Blanks
Section C: True or False
Section D: Short Answer Questions
Pollution is when harmful materials make our environment dirty and unhealthy. Air pollution can make us sick if we breathe in dirty air, and it can also make the air hotter, increasing the Earth’s temperature. Water pollution happens when waste from factories is released into water bodies, and also when people throw trash into rivers or oceans. ‘Reuse’ means to use something over and over again instead of throwing it away after just one use. We should avoid bursting crackers during festivals because they release smoke and poisonous gases into the air, causing air pollution, and they also create loud unwanted noise, causing noise pollution. Section E: Diagram-Based Questions
One source of air pollution shown is the factory emitting thick black smoke, or the car releasing exhaust fumes. Evidence of water pollution in the river includes plastic bottles floating on the surface and a pipe discharging murky liquid. The loud speaker symbol suggests noise pollution. One item causing land pollution is the scattered garbage like food wrappers or old newspapers. Section F: Long Answer Questions
Conservation of the environment means actively taking care of our Earth, including its air, water, plants, animals, and humans. It is important because the environment provides us with all the essential resources we need to live, such as oxygen, water, and food. By conserving, we ensure that these vital resources are protected from harm caused by human activities and are available for future generations, maintaining a healthy planet for everyone. Three actions to help save the environment are: First, plant trees because they help clean the air. Second, reduce the use of vehicles by walking or cycling for short distances to lessen air pollution. Third, always dispose of waste properly in bins and avoid using plastic bags, opting for cloth bags instead, to prevent land pollution. These actions contribute to cleaner air, land, and water. Section G: Environmental Awareness / Everyday Use
Using an eco-friendly cleaner made from vinegar, baking soda, and water is better for the environment than chemical cleaners because it avoids releasing harmful chemicals into our drains and eventually into water bodies. Chemical cleaners can pollute water, harm aquatic life, and may even affect human health, whereas natural ingredients are biodegradable and safe for the ecosystem. 
Answer key