CBSE Class 5 Environmental Studies Environmental Concerns Pollution, Global Warming and Food Chains Worksheet Set 05

Answer: (b) Ozone. The ozone layer absorbs most of the Sun's harmful ultraviolet rays.

Teacher's Note:
1. Read all the options before choosing.
2. Link the correct choice with the cause or effect given in the question.

Answer: (c) Glaciers. Water from melting glaciers and ice caps flows into the oceans.

Teacher's Note:
1. Read all the options before choosing.
2. Link the correct choice with the cause or effect given in the question.

Answer: (a) Air conditioners. CFCs used in some old cooling devices damage the ozone layer.

Teacher's Note:
1. Read all the options before choosing.
2. Link the correct choice with the cause or effect given in the question.

Answer: (a) Methane. Methane traps heat in the atmosphere.

Teacher's Note:
1. Read all the options before choosing.
2. Link the correct choice with the cause or effect given in the question.

Answer: (b) CNG. CNG burns more cleanly and gives out less smoke than petrol or diesel.

Teacher's Note:
1. Read all the options before choosing.
2. Link the correct choice with the cause or effect given in the question.

Answer: False. It affects the whole Earth by changing weather, melting ice and raising sea levels.

Teacher's Note:
1. Think about the cause and effect before you decide.
2. Correct a false statement by changing the key idea.

Answer: True. Industrial waste pollutes water and harms living things.

Teacher's Note:
1. Think about the cause and effect before you decide.
2. Correct a false statement by changing the key idea.

Answer: True. Trees take in carbon dioxide and release oxygen.

Teacher's Note:
1. Think about the cause and effect before you decide.
2. Correct a false statement by changing the key idea.

Answer: True. Rising sea levels can flood low coastal areas.

Teacher's Note:
1. Think about the cause and effect before you decide.
2. Correct a false statement by changing the key idea.

Answer: False. Burning them releases greenhouse gases, so we should use cleaner energy sources.

Teacher's Note:
1. Think about the cause and effect before you decide.
2. Correct a false statement by changing the key idea.

Answer: Air pollution is the mixing of harmful gases, smoke and dust in the air. It is caused by vehicles, factories and burning of waste and makes breathing difficult.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Global warming is the slow rise in the average temperature of the Earth. It happens when too many greenhouse gases trap the Sun's heat.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Gases such as carbon dioxide and methane trap some of the Sun's heat near the Earth, keeping it warm. Too much of these gases makes the Earth warmer than it should be.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Water pollution is the mixing of harmful substances such as sewage, chemicals and garbage in water bodies. It makes water unsafe for people, animals and plants.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: A food web is a network of many food chains that are linked together in a community. It shows that one living thing can be eaten by, and can eat, several others.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Plants need sunlight, air, water and soil, which are non-living. Animals depend on plants and other animals for food, and dead plants and animals return nutrients to the soil.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: A food chain shows how energy passes from one living thing to another through eating. Example: grass → grasshopper → frog → snake.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Pollution is the addition of harmful substances to the air, water or soil. Its types are air pollution, water pollution, soil pollution and noise pollution.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Greenhouse gases are gases that trap heat in the atmosphere. Examples are carbon dioxide, methane and water vapour.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: Glaciers and polar ice melt and sea levels rise. Weather patterns change, with more floods, droughts and heat waves, and coastal areas may go under water.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.

Answer: 1. Plant and look after trees.
2. Use public transport, cycle or walk for short distances.
3. Do not throw garbage in water bodies or on the roads.

Teacher's Note:
1. A good answer defines the term and gives one example or effect.
2. Write in your own words and keep it short.