(i) Like human being, animals also depend on plants for their necessity.
(ii) Silk worm eat mulbery leaves and produce silk.
(iii) Animals, insects and birds help in cross pollination.
(iv) Entering of insects into the flower leads to pollination. It increases yield of crop.
(v) Plants and algae living in coral reefs are the food variety of fishes and fisheries work is done in these areas.
(vi) Animals and plants are play an important role in spreading of seeds.

AVOID:
Avoid the usage of unwanted materials which create more debris.
(e.g) (i) Avoid buying packaged foods.
(ii) Refuse to buy use and throw plastic products.
REDUCE:
We can reduce the waste by using durable goods that last longer instead of things that are used once and thrown away.
(e.g) (i) Write both sides of papers.
(ii) Instead of unnecessary printing use electronic facilities.

Aim: Soap manufacturing.
Requirements:
i) 35 ml of water.
ii) 10 ml of NaOH.
iii) 60 ml of coconut oil.
Procedure:
i) Cover your work area with old newspaper.
ii) Take 35 ml of water in a jar.
iii) Add 10 gram of concentrated NaOH and allow it to cool.
iv) Then add 60 ml of coconut oil drop by drop and stir it well.
v) On getting dried, soap can be obtained.

(i) Direct collection and use of rain water is called rainwater harvesting.
(ii) Excellent and valuable source of water in emergencies.
(iii) Ideal solution for inadequancy of water.
(iv) Increase ground water level.
(v) Reduces rainwater run off and solves drainage problems in houses.

(i) Potable water is the water which is safe to drink. On an average the human body requires 2-3 liters of water per day for proper functioning.
(ii) It is transparent.
(iii) It is odourless and colourless.
(iv) Cleaned of harmful contaminants.
(v) It is harmless or free from disease causing bacteria.

i) Place the iron needle on a table. Now take a bar magnet and place one of its poles near one edge of iron needle and rub from one end to another end without changing the direction of the pole of the magnet. Repeat the process for 30 to 40 times.
ii) Bring a pin or some iron filings near the iron needle to check whether it has become a magnet. Does the iron needle attract the pin / Iron filing? If not continue the same process for some more time.

(i) When there is no pond or lake in an area formation of clouds will be possible.
(ii) Transpiration from the arial parts of all plants and trees will evaporate water and it will form clouds.

a) When we place the bar magnet near the iron filings large amount of iron filings stick on the two ends of the bar magnet. These ends are poles of the magnet.
b) Poles will attract more iron filings, because poles have high magnetic strength.

Neem tree, Tulsi, Amla.

(a) Loud Speaker - Noise pollution
(b) Plastic - Land pollution

Ecosystem is a community of living and non-living things that work together.

i) water loving side
ii) water hating side

The cold surface of the bottle containing icy water cools the air around it and the water vapour of the air condenses on the suface of the bottle. This process is also the result of condensation of water vapour.

Hardware: Hardware is the parts of a computer which we can touch and feel.
Software: Software are programmed and coded applications to process the input information.

(i) Neem trees give shadow and it purifies the air in the form of oxygen.
(ii) Leaves and other waste of this plant is used as fertilizer.
(iii) Oil and cake is derived from seeds of this plants is used as natural pesticides.
(iv) Juice of its leaves are used to treat pox like disease.

(i) Learning food chain help us to understand the feeding relationship and interaction between organisms in any ecosystem.
(ii) Understanding the food chain also helps us to appreciate the energy flow and nutrient circulation in an ecosystem.
(iii) The food chain can be used to understand the movement of toxic substances and their impacts.

(i) Earthworms take organic wastes as food and produce compost castings.
(ii) They improve the soil health and consequently plant health.
(iii) Because of the multitude of services, Earthworms are known as Farmer's friend.

71% of earth's surface is covered with water. The fresh water is only 3%. It remains the same, But the water needed for plants, animals and man is increasing day by day. So we face water scarcity.