Course Content
LESSON 1 : Story of the past
0/1
LESSON 2 : Sources of history
0/1
Lesson 3 : Timelines and calendars
0/3
Lesson 4 : A Good Citizen
Lesson 4 : A Good Citizen
0/1
LESSON 5 : The four domains of the earth.
0/2
LESSON 10 : political divisions of north India
0/4
LESSON 11 : political divisions of east India
0/3
LESSON 12 : political divisions of north east India
0/3
LESSON 13 : Political divisions of central India
0/3
LESSON 14 : political divisions of western India
0/3
LESSON 15 : political divisions of south India
0/4
LESSON 17 : our environment – pollution and protection
0/3
Class 4 – Social Science
    About Lesson

    Answer the following. 

    1. What is pollution? Name different types of pollution. 

    Ans. Pollution is the process of adding harmful substances to the environment. Air pollution, water pollution, noise pollution and soil pollution. 

    2. What do you mean by biodegradable waste and non biodegradable waste ?

    Ans.  Waste that can be broken down by bacteria into very small particles and become part of the soil again are called biodegradable waste. Eg : kitchen waste, vegetable peel, paper. 

    Non biodegradable waste cannot be broken down. It remains as it is for hundreds of years. Eg: plastic, glass. 

    3. What problems does an oil spill create ?

    Ans. When an oil spill occurs in an ocean or sea, it harms fish, other water creatures and sea birds.

    4. What problems can more vehicles on the road create  ?

    Ans. More vehicles on the road can create problems like raising noise levels and also lead to air pollution due to burning of fuel.

    5. What are the 3 R’s to preserve our environment and reduce pollution  ?

    Ans. The 3 R’s are  :

    Reduce – when we together reduce some of the things we use or change the ways of using,we can reduce pollution. 

    Reuse – instead of throwing away reusable things, we can reuse them. 

    Recycle – Recycling is a process by which used goods are changed to make new material. Eg : paper can be recycled to make cardboard boxes or newspaper. 

    6. Write how we reuse things in our daily life. 

    Ans. Cloth shopping bags can be used several times. 

    Old clothes, books and toys can be donated to others who can use them. 

    Envelopes and opposite side of used papers can be used as notepads.

    Newspaper can be painted and used as gift wrapper.

            ××××××××××××××××××××××××××××××