Can You Tell Me the Story?
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Tapescript s
Activities 7, 8 and 9
Activity 11
A. The process that leads to acid rain begins with the burning of fossil fuels. Burning, or
combustion, is a chemical reaction in which oxygen from the air combines with carbon,
nitrogen, sulfur, and other elements in the substance being burned. The acid compounds
are carried by air currents and the wind, sometimes over long distances. When clouds
or fog form in acid-laden air, they too are acidic, and so is the rain or snow that falls
from them.
B. Evaporation is an important part of the earth’s water cycle, the continual movement
of fresh water between the earth’s surface and its atmosphere. The water rises into
the atmosphere, condenses in clouds, and falls back to the earth as precipitation. This
precipitation replenishes streams, rivers, lakes, groundwater reservoirs, and other
freshwater supplies.
C. Carbon cycle is the cycle of carbon usage by which energy
Á ows through the earths ecosystem. The basic cycle begins when
photosynthesizing plants use carbon dioxide CO2 found in the atmosphere
or dissolved in water. Some of this
carbon is incorporated in plant tissue as carbohydrates, fats, and protein; the rest
is returned to the atmosphere or water primarily by aerobic respiration.
D. For more than a century scientists have known that certain gases in the atmosphere-most
notably water vapor, carbon dioxide, and methane-contribute to atmospheric warming.
These greenhouse gases, which also include nitrous oxide and chloro
Á uorocarbons, allow about half of the short-wave radiation
in sunlight to pass through the earth’s atmosphere, heating the earth’s surface. At
the same time, greenhouse gases absorb and reradiate most of the longer wavelengths of
radiation, such as infrared radiation, which is emitted by the earths warmed surface. This
heat-trapping capacity of the atmosphere is popularly known as the
greenhouse effect.
Taken from Microsoft Encarta Reference Library, 2008
Activities 12 and 13
What causes rainfall, where does the water come from and where does it go? The answers to
these questions lie in the water cycle. The cycle begins when the sun causes the evaporation of
water from the world’s oceans, lakes and rivers. The water is changed into small droplets called
water vapor. This evaporated water gathers in the atmosphere. As this moisture-laden air rises,
it cools and condenses, forming clouds. As the amount of water vapor grows in the air, rain
clouds form and the water is returned to earth as precipitation rain, hail or snow. The water
then
Á ows back to the rivers, lakes and oceans, where the process begins all over again
Taken from SOSE: Studies of Society Environment,
2000
The water
1
cycle is the never-ending movement of the earth’s water. Water goes from
2
the ocean to the air to the land and
3
back to the oceans again. For that reason, its
4
movements is called a cycle.
This cycle
5
begins when heat from the sun turns ocean water into
6
water vapour. Water vapour is water that has become
7
a gas. The water vapour rises high into
8
the sky, where it cools off. The cooled water vapour changes into
9
tiny drops of water. The drops are held up in the sky by rising
10
warm air. When billions of these drops of water
11
cluster together they form
12
a cloud. The water in the clouds eventually
13
falls to earth as rain. If the water vapour is
14
cold enough, it turns into ice an falls as
15
snow. Most rain and snow falls into the ocean, but
some falls on
16
land. In time, this water also
17
Á ows back to the ocean and the
18
cycle starts again.
Taken from The World Book Student Discovery Encyclopedia,
2006
230
Developing English Competencies f or Grade XII of Language Programme
Didu : It’s just that? Transgenic maize has the same taste as common corn.
Tami : It’s not only the reason some fear that certain types of genetically engineered
crops will further reduce biodiversity in the cropland. Is that clear?
Didu : Yes, I see the point. By the way, what’s your opinion on GMO?
Tami : Let me just say that I oppose it, for any reasons. I wish we could insist on a ban
on GMO.
Dialogue 2 Nisa : Hi. I wonder if you would mind
answering a question for me. Maya : OK, what’s the question?
Nisa : Do you approve of genetically modi À ed
food? Maya : Well, I don’t think GM food is good for
us. Nisa : So your answer is “no”.
Maya : That’s right. I’m against it. Nisa : OK, thank you, Maya.
Maya : No problem.
Activities 7 and 8
Paragraph 1 Genetic engineering, genetic modification,
and gene splicing are terms for the process of manipulating genes in an organism. It has important
uses, but many people are worried by it. Paragraph 2
Proponents of genetic engineering argue that the technology is safe, and that it is necessary
in order to maintain food production that will continue to match population growth.
However, others argue that food distribution, not production, is the biggest problem.
Paragraph 3 Others oppose genetic engineering on
the grounds that genetic modification may have unforeseen consequences in the modi
À ed organisms and their environments. The ecological
and environment effects of transgenic plants are constantly being investigated.
Paragraph 4 Anti-genetic-engineering activists say that
with current recombinant technology there is no way to ensure that genetically modi
À ed organisms will remain under control, and the use
of this technology outside of secure laboratory environments carries unacceptable risks for the
future.