Short Answer type
Questions:-
Q1. Name the
continents in increasing order of their size.
Ans. Names of the
continents in increasing order of their size are as follows:-
Australia, Europe, Antarctica,
South America, North America, Africa, Asia.
Q2. Name the oceans in
increasing order of their size.
Ans. Names of the
oceans in increasing order of their size are as follows:-
Arctic ocean, Indian ocean,
Atlantic ocean, Pacific ocean.
Q3. What is the
composition of the atmosphere?
Ans. Clean dry are contains 78% of Nitrogen, 21% of
Oxygen and 1% other gases, like- Caron dioxide, neon, ozone, hydrogen, etc.
Water vapour, dust particles,
smoke, salt, etc. are also present in air.
Q4. Name the different
layers of the atmosphere.
Ans. Different layers
of atmosphere are as follows:-
-
Troposphere
-
Stratosphere
-
Mesosphere
-
Thermosphere
-
Exosphere
Q5. What are the main
elements of the biosphere?
Ans. Plants, animals,
human beings and microbes are some important components of biosphere, which are
interdependent on one another.
Long Answer type
questions:-
Q1. Write about at
least one important physical feature of each continent.
Ans. Important physical feature of each continent
are as follows-
-
Asia- Himalaya
is the highest mountains and the Tibet is the highest plateau of the world is
found here.
-
Africa- it has Vast desert like- Sahara and Great
Rift valley.
-
North
America- Western costal area contain
high mountains and plateaus, which is the part of ring of fire of pacific
ocean.
-
South
America- Andes mountains spreading through the west coast from Caribbean sea in
the north to Cape Horn in the south.
-
Antarctica-
this continent is always covered under thick layer of ice, so it is also called
White continent.
-
Europe-
This continent has alpine system which is a chain of high mountains extending
from the Atlantic ocean in the west to the Caspian sea in the east.
-
Australia-
The Great barrier reef is a found here along the north eastern coast, which is
built by corals.
Q2. What is the
importance of oceans for human beings?
Ans. The importance of
oceans for human beings is as follows:-
-
It is the
main source of moisture in atmosphere.
-
It also regulates
the atmospheric temperature.
-
It is the source
of various kinds of minerals and chemicals.
-
It is also the main source of fish and other
marine life.
-
It provides
free and permanent route for travel and trade.
-
Tidal energy
is used to generate electricity.
-
Common
salt is obtained from the ocean.
-
Shortage
of drinking water can be solved by treating ocean water.
Q3. What is the
importance of the atmosphere?
Ans. Importance of the atmosphere is as follows:-
-
It
prevents sun’s radiation and ultraviolet rays from reaching to earth surface.
-
It acts
like a greenhouse and keeps earth surface warm and prevent the extremes of
temperature during day and night.
-
Atmospheric
pressure depends upon the temperature and pressure difference between two
places cause wind, movement of wind helps in condensation of moisture and
precipitation.
-
Weather
changes are result of presence of atmosphere around the earth surface.
-
Sound
waves are transmitted due to presence of air.
Q4. How are human
beings disturbing the delicate balance of nature?
Ans. Human beings are completely dependent on
nature for fulfilling all their needs. Excessive use of natural resources cause
pollution in the environment, such as-
-
Burning of
fossil fuel cause environmental pollution and causing acidic rain.
-
Deforestation
for timber and agricultural land cause global warming, land erosion and
destroying wild life.
-
Use of
fertilizers and insecticides causing water pollution and disturbing aquatic
life.
-
Hunting of animals and cutting of forest has
made many species extinct and many are endangered.
-
Waste
material produced by the humans dumped over the land and causing degradation of
land.
