Download Living Things and the Environment

Living Things and
the Environment
Seventh Grade
Chapter 22-1
Ecosystems
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All the living and
nonliving things that
interact in a particular
area make up an
ecosystem.
Some examples of
ecosystems are
mountains, oceans,
desserts, and forests.
Habitats
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A habitat is a specific
place in an ecosystem
where an organism
obtains food, water,
shelter, and other
things it needs to live,
grow, and reproduce.
A single ecosystem
may contain many
habitats.
Habitats cont.


Some examples of
habitats in a forest
ecosystem are plants
growing in the damp
soil, bears on the forest
floor, and birds in nests
at the top of a tree.
Organisms live in
different habitats
because they have
different requirements
for survival
Biotic and Abiotic
Factors
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The living things of
an ecosystem are
called biotic factors.
Examples:
- grass, plants,
hawks, badgers,
worms, fungi, and
bacteria that all live
in the same
ecosystem
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The nonliving things
in an ecosystem
are called abiotic
factors.
Examples:
- water sunlight,
oxygen,
temperature, and
soil.
Water
Water is very important to all
organisms.
 The human body is made up of about
65% water.
 Plants and algae use water, along with
sunlight and carbon dioxide, to make
food in a process called
photosynthesis.

Sunlight and Oxygen
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Sunlight is necessary for photosynthesis
which is important because without plants or
algae to provide a source of food, few other
organisms would live.
Most living things require oxygen to carry
out their life processes.
Organisms on land obtain their oxygen from
the air while fish and other water organisms
obtain dissolved oxygen from the water.
Temperatures and Soil

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Temperatures that are typical of an area
determine what can live there.
Some animals alter their environments to
overcome very hot or very cold
temperatures.
The type of soil in an area influences the
kinds of plants that can grow there.
Some organisms make their homes in the
soil.
Population


All the members of
one species in a
particular area are
referred to as a
population.
Studying the
population is hard
to do without a
specified area. Ex.
(Charlotte County)
Community

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All the different
populations that live
together in an area
make up a community.
In a community the
different populations
must live close enough
together to interact with
one another.
They interact by using
the same resources,
such as, food and
shelter.
Levels of Organization
The smallest unit of organization is a
single organism, which belongs to a
population of other members of its
species.
 The population belongs to a
community of different species.
 The community and abiotic factors
together form an ecosystem.

Ecology

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The study of how
living things interact
with one another
and with their
environment is
called ecology.
Ecologists study
how organisms
react to changes in
their environment.