NCERT 5th Class (CBSE) Science: Our Environment

Question: What do you understand by pollution?

Answer: Harmful change mode in the environment due to human activities is called pollution.

Question: Name the four kinds of pollution?

Answer: The four kinds of pollution are:

1. Air pollution
2. Water pollution
3. Land pollution
4. Noise pollution

Question: How does air pollution harm us?

Answer: Air pollution harms us as it causes a number of deadly diseases like lung cancer and asthma. Industries and winds are the main sources of air pollution.

Question: Describe the different types of pollution?

Answer: The different types of pollution are:

1. Air pollution: Industries and winds are the main source of air pollution. Burning of garbage also bads to air pollution. Air pollution may cause a number of deadly diseases like lung cancer etc.
2. Water pollution: Industries are a major source of water pollution. Household and industrial wastes released into water bodies pollution them. Activities like washing clothes or bothing animals in revers, especially in rural area, also cause water pollution.
3. Land pollution: Dumping of solid wastes like plastic bags, glass, bottles and metal containers causes land pollution. roots of trees hold the soil together. Deforestation causes strong wind and water to carry soil particles away leading to sail erosion.
4. Noise pollution: Vehicles, load speakers etc, are the sources of noise pollution. Exposure to loud noise over a long period of time may even cause deafness.

Question: What are the main causes of air and water pollution?

Answer: Causes of air pollution are:

1. Exhaust from combustion engines
2. Use of coal and fossil fuels and petroleum
3. Chemical pesticides, fertilizers dust
4. Radio active fall out
5. smoke and poisonous gases that wine out from vehicles and industries

Causes of water pollution are:

1. Solid waste
2. domestic waste
3. livestock animal
4. sewage  industry
5. septic tank sewage and land erosion

Question: How is noise pollution harmful to us?

Answer: Noise pollution is harmful to us in following ways:

1. It inter fares with spoch as in its presence we may not be able to listen to others.
2. It can cause permanently damage in hearing.
3. It causes headaches, blood presence, heart failure.
4. It increases heart beat.