Kendriya Vidyalaya Sangathan, Chennai Region
Summative Assessment - II – 2015
Open Text Based Assessment
CLASS
: VI
SUBJECT: SCIENCE
THEME 1 -AIR POLLUTION
We can survive for some time without food, but we cannot survive even for a fewminutes
without air. This simple fact tellsus how important clean air is to us. Air consistsof a mixture
of gases. By volume, about 78% of this mixture is nitrogen and about 21% is oxygen. Carbon
dioxide, argon, methane, ozone and watervapour are also present in very small
quantities.When air is contaminatedby unwanted substances which have a harmful effect on
both the living and the non-living, it is referred to as air pollution.
How does Air Get Polluted?
The substances which contaminate the air are called air pollutants. Sometimes, such
substances may come from natural sources like smoke and dust arising from forest fires or
volcanic eruptions. Pollutants are also added to the atmosphere by certain human activities.
The sources of air pollutants are factories, power plants, automobile exhausts and burning of
firewood and dung cakes. Many respiratory problems are caused by air pollution.
Vehicles produce high levels of pollutants like carbon monoxide, carbon dioxide, nitrogen
oxides and smoke. Carbon monoxide is produced from incomplete burning of fuels such as
petrol and diesel. It is a poisonous gas. It reduces the oxygen-carrying capacity of the blood.
A thick fog-like layer in the atmosphere, especially during winters is smog which is made up
of smoke and fog. Smoke may contain oxides of nitrogen which combine with other air
pollutantsand fog to form smog. The smog causes breathing difficulties such as asthma,
cough and wheezing in children. Many industries are also responsible for causing air
pollution. Petroleum refineries are a major source of gaseous pollutants like sulphur dioxide
andnitrogen dioxide. Sulphur dioxide is produced by combustion of fuels like coal in power
plants. It can cause respiratory problems, including permanent lung damage.
Other kinds of pollutants are chlorofluorocarbons (CFCs) which are used in refrigerators, air
conditioners and aerosol sprays. CFCs damage the ozone layer of the atmosphere. The ozone
layer protects us from harmful ultraviolet rays of the sun. In addition to the above
mentionedgases, automobiles which burn diesel and petrol also produce tiny particles which
remain suspended in air for long periods. They reduce visibility. When inhaled, they cause
diseases. Such particles are also produced during industrial processes like steel making and
mining. Power plants give out tiny ash particles whichalso pollute the atmosphere.
THEME II - WATER
Water is an important natural resource. Living things, both plants and animals, cannot live
without water. We use water every day for various purposes – cooking food, washing,
drinking, cleaning, irrigation, in industries and many other activities. We consume a lot of
water every day. About 70% of our body consists of water. Water is available to us from two
sources, surface water and underground water or subsoil water.
Water has played a prominent role in the development of civilizations. Countries with good
water availability have progressed much faster. The Indus – valley civilization and the Nile –
river civilization are some of the examples.
Pollution of water by human activities and throwing industrial waste, garbage and sewage in
water bodies has increased considerably. This has deteriorated the quality of available fresh
water.
Scarcity of water has now become a common feature during summer. The present situation
requires proper management and conservation of water resources. Water is precious and life
is not possible without water. We have to do a lot to conserve water resources for the future.
We should adopt water harvesting techniques to recharge ground water. An average urban
family uses 640 litres of water per day. The toilet is the biggest user of indoor water. On an
average, it uses 11 litres of water per flush. Water is a gift of nature to mankind. Wise and
judicious use of water can help in conservation of water.
केन्द्रीय विद्यालय संगठन चेन्द्नई क्षेत्र
KENDRIYA VIDYALAYA SANGATHAN CHENNAI REGION
सम्मेटिि असेस्में ि माचच 2015 SUMMATIVE ASSESSMENT 2 MARCH 2015
कक्षा 6 CLASS VI
अधिकतम अंक :10
विषय :सामाजिक विज्ञान
SUB: SOCIAL SCIENCE
MAX MARKS: 10
TIME : 30mins
OTBA
There are two themes given below selected from history and geography lessons: Each
theme carry five marks
Study the given paragraph carefully and answer the following questions
THEME I- The story of the monkey king
Once upon a time there was a great monkey king, who lived on the banks
of the Ganga in the Himalayas, with 80,000 followers. They fed on the fruit of a
special mango tree, which were very sweet. Such exquisite mangoes did not
grow on the plains. One day, a ripe mango fell into the river and floated all the
way to Varanasi.
There the king of the city who was bathing in the river found it, and was
amazed when he tasted it. He asked the foresters of his kingdom whether they
could find the tree for him, and they led him all the way to the Himalayas.
There, the king and his courtiers had their fill of mangoes. At night, the king
discovered that the monkeys were also feasting on the fruit, and decided to kill
them.
However, the king of the monkeys worked out a plan to save his
followers. He broke off branches of the mango tree, and tied them to form a
‘bridge ’across the river, and held on to one end till all his followers crossed
over. Exhausted with the effort, he fell down and lay dying.
The human king saw what had happened, and tried unsuccessfully to
revive the monkey. When he died, the king mourned his death and paid him full
respect.
This story is shown on a piece of sculpture found from a stupa at Bharhut in
central India.
THEME II - Forests and Wild life
Forests are very useful for us. They perform various functions. Plants
release oxygen that we breathe and absorb carbon dioxide. The roots of the
plants bind the soil; thus, they control soil erosion.
Forests provide us with timber for furniture, fuel wood, fodder, medicinal
plants and herbs, lac, honey, gum, etc. Forests are the natural habitat of wild
life. Natural vegetation has been destroyed to a large extent because of the
reckless cutting of trees. We should plant more trees and protect the existing
ones and make people aware of the importance of trees. We can have special
programmes like Van Mahotsav to involve more people in making our earth
green.
The tiger is our national animal. It is found in various parts of the
country. Gir forest in Gujarat is the home of Asiatic lions. Elephants and onehorned rhinoceroses roam in the forests of Assam. Elephants are also found in
Kerala and Karnataka. Camels and wild asses are found in the Great Indian
desert and the Rann of Kuchchh respectively. Wild goats, snow leopards,
bears, etc. are found in the Himalayan region. Besides these, many other
animals are found in our country such as monkey, wolf, jackal, nilgai, cheetal,
etc. India is equally rich in bird life.
The peacock is our national bird.
Other common birds are parrots, pigeons, mynah, geese, bulbul and ducks.
There are several bird sanctuaries which have been created to give birds their
natural habitat. These provide the birds protection from hunters.
There are several hundreds of species of snakes found in India. Cobras
and kraits are important among them. Due to cutting of forests and hunting,
several species of wildlife of India are declining rapidly. Many species have
already become extinct. In order to protect them many national parks,
sanctuaries and biosphere reserves have been set up. The Government has also
started Project Tiger and Project Elephant to protect these animals.
You can also contribute in conserving wildlife. You can refuse to buy
things made from parts of the bodies of animals such as their bones, horns, fur,
skins, and feathers. Every year we observe wildlife week in the first week of
October, to create awareness of conserving the habitats of the animal kingdom.