Where Did It All Begin

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Where Did It All Begin?
Before there was any life on Earth, the world
was a bleak and rocky globe with only shallow
seas and a thin layer of gas. The earth was a
very desolate and hostile place. This type of
environment is called an inorganic state.
Energy from the sun bombarded the surface of the
Earth. In time, millions of years later, the sun
produced chemical and physical changes on the
Earths surface and this resulted in the first
evidence of life.
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In The Beginning
The first living creatures on earth were
formless, jelly-like blobs. These tiny creatures
could collect life-giving energy from the Sun.
They were also capable of reproduction which
meant that they could continue to produce more
living creatures.
This generation of life formed the first
community and established what is called the
zone of life. Here the matter of the Earth was
used to make living substance.
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The Zone of Life
Then, like now, living creatures needed certain
things to live, grow, and reproduce. Water was
one of the major elements. All living creatures
depend on water for life to continue. Other
essential elements include those gases and
elements found in the air. And of course, the
life giving energy of the Sun
In addition to these essential elements, all life
on Earth depends on green plants to live. Plants
use sunlight to produce food which feeds animals.
This process is called photosynthesis. Plants
also provide oxygen. Most animals require oxygen
for respiration.
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Ecosystems
During this time, living organism produced large
numbers of a few kinds of living creatures.
Soon plants and animals of all kinds evolved.
Families or communities developed so that certain
plants grew with other plants. Animals
associated with the plants and with one another
to form communities.
These communities included forests, grasslands,
deserts, dunes, bogs, rivers, and lakes. Soon
the living community and their nonliving
environment became inseparable, interrelated, and
constantly interacted with one another. The
living community and the nonliving environment is
called an ecosystem.
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Kinds of Ecosystems
There are two kinds of ecosystems.
Aquatic Ecosystems are those involving marine
environments and freshwater environments on the
lands.
Terrestrial Ecosystems consist of forest,
grasslands, deserts, and tundra.
There are particular animals that thrive in each
type of ecosystem.
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What Is Pollution?
Pollution is the result of adding substances or
forms of energy to the environment at a rate that
is faster than the environment can accommodate
its disposal.
Pollution has been a fact of life since groups of
people first congregated and remained in one
place for long periods of time. But pollution
was not a serious problem as long as there was
enough space available for each individual or
group. With the establishment of communities,
pollution became a problem. This occurred as
early as ancient times. With the rise of
technology, the spread of industrialization, and
the increase in human population, pollution has
become a universal problem.
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Types of Pollution
Pollutants are those elements responsible for
pollution. They are classified according to the
part of the environment they affect.
Air Pollution is a result of substances being
released into the air in large quantities. These
substances include gases, finely divided solids,
or finely dispersed liquid aerosols.
Water Pollution is caused by the accumulation in
oceans, lakes, streams, and ground water. The
major causes of water pollution include sewage,
industrial waste, garbage and refuse, and
agricultural fertilizers such as pesticides and
herbicides.
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What is Pollution??
Water Pollution is caused by the accumulation in
oceans, lakes, streams, and ground water. The
major causes of water pollution include sewage,
industrial waste, garbage and refuse, and
agricultural fertilizers such as pesticides and
herbicides.
Land Pollution is caused by the deposition on
land of solid waste that cannot be broken down
completely or in some cases cannot be broken down
at all. These include such as cans, bottles,
plastic containers, paper, and used cars.
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Endangered Species
Resources
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Just For Fun!!
Classify the images below as either air, water or
land pollution. You will be able to check your
answers once you have completed the slide show.