Page 99 - Active Science 5 Ebook and Activity
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it dirty. These dust particles enter our nose
        and eyes that cause irritation. They can

        also be the carrier of germs. Air pollution
        causes many respiratory diseases like
        cough, asthma, lung cancer and many
        other breathing problems.




        Let’s Recapitulate

            Fill in the blanks.
            1.  All the things that surround us make our ________________.
            2.  Pollution causes harmful effects on ________________.

            3.  The presence of ____________, _____________ and ___________ causes air pollution.
            4.  In rural areas, people use ____________ and _____________ for cooking.

            5.  Dust particles in the environment enter our _________ and _________ that cause irritation.



        Greenhouse Effect: When harmful gases like carbon dioxide, chlorofluorocarbons and
        methane trap solar energy and do not allow it to escape from the atmosphere, it causes
        Greenhouse Effect.

                                                                                           Factual Study
                                                        The Greenhouse Effect              Motor vehicles release

                                 Some solar radiation is                                   carbon monoxide in
                                 reflected by the Earth and the
                                 atmosphere.                                               the air. When we
                                                     Some of the infrared radiation passes   breathe this polluted
                                                     through the atmosphere. Some is absorbed
                                                     and re-emitted in all directions by   air, carbon monoxide
                                                     greenhouse gas molecules. ·The effect of
                                                     this is to warm the Earth’s surface and the   goes into the blood and
                                                     lower atmosphere.
           Most radiation is              Atmosphere                                       reduces the capacity of
           absorbed by the                                        Infrared radiation       blood to carry oxygen.
           Earth’s surface and            Earth’s surface         is emitted by the
           warms it.                                              Earth’s surface.         This makes the person
                                                                                           feel weak and easily
                                                                                           tired.

        The addition of carbon dioxide in air

        because of air pollution, has increased the
        temperature of earth. This is called Global
        Warming. Due to global warming, glaciers
        have started melting. Therefore, it has

        resulted in the rise of water level of oceans
        which increases the chances of floods.




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