Organisms and the
Environment
Chapter Four: Physical Science
Connections
• 4.1 Elements and Compounds
• 4.2 The Compounds of Life
• 4.3 Physical Variables
4.3 Ecosystems and habitats
• Organisms belong to
larger systems that are
dependent on one
another and function
together.
• The biosphere is
Earth’s life-supporting
layer of land, water,
and air.
4.3 Ecosystems and habitats
• An ecosystem is
made up of groups of
living things and their
physical surroundings.
4.3 Ecosystems and habitats
• A habitat is a place where a particular
type of organism lives.
• This fish’s habitat is
the ocean.
4.3 Variables in Habitats
• Individual living things are made up of
many small systems that work together.
• Each system has a structure (its parts)
and a function (a job).
What is the
structure in the
goldfish that
functions to
pump blood to
it’s muscular tail?
What is the
function of the
fish’s gills?
4.3 Land habitats
• Many variables affect
life on land.
• Five important
variables are:
1. temperature
2. precipitation
3. sunlight
4. type of soil
5. oxygen
What variables can you see in
these two different habitats?
4.3 Land habitats
• Soil is a mixture of
decayed plant and
animal parts and very
small rock particles.
• The type of soil varies
in different land
habitats.
4.3 Freshwater habitats
• Water covers 71% of
Earth’s surface.
• Less than 0.01% of
Earth’s water is found
in freshwater habitats
on the Earth’s surface.
What is the source of most
of the planet’s water?
4.3 Freshwater habitats
• pH is a measure of chemicals called
acids and bases in water.
• pH ranges from 0 to 14.
• Pure water is pH 7 (neutral).
4.3 The oceans
• Scientists divide the oceans into zones.
4.3 The oceans
• Most life in the oceans is
concentrated in zones
where light can penetrate.
• Life is difficult for
organisms in the deep
zones.
• Some organisms are able
to produce their own light.
For what purpose do these
organisms produce their
own light?
Investigation 3A
Living Conditions
• How will similar populations react to different
living conditions?
Chemistry Connection
Chef or Scientist?
• Measure accurately,
stir, heat, carefully
observe, and don’t
stick your finger in
anything.
Activity
What’s on your Label?
• Food packages are
required by law to
have nutrition facts
labels.
• In this activity, you
will study some
breakfast cereal
labels.