Transcript 3.4 Cycles of Matter

3.4 Cycles of Matter
-Matter cannot be created or destroyed, it
changes.
-biological processes-all activties performed
by living organisms (breathing, “burning”
food, & eliminating waste products)
-geological processes-volcanic eruptions,
formation & breakdown of rock, & major
movements of matter.
-chemical & physical processes-formation
of clouds & precipitation, the flow of
running water, & lightning.
-Human activity-mining & burning of fossil
fuels, clearing of land for building &
farming, burning of forests, & the
manufacture & use of fertilizers.
The Water Cycle
-water molecules enter the atmosphere as
water vapor when they evaporate from the
ocean or other bodies of water or by
evaporating from leaves (transpiration)
-if this air cools, water vapor condenses
into tiny droplets that form clouds. When
the droplets become large enough, they
fall to the Earth's surface as precipitation
(rain, snow, sleet or hail)
-on land, some precipitation flows along the
surface (runoff) until it enters a river or
stream that carries it to a lake or ocean.
-it can also be absorbed into the soil
(groundwater)
~enters plants through their roots or
flows into larger bodies of water or
penetrates deeply enough into the
ground to become part of underground
reservoirs.
Nurtrient Cycles
-nutrients-chemical substances that an
organism needs to sustain life
~every organism needs nutrients to
build tissues & carry out life
functions.
The Nitrogen Cycle
-all organisms need nitrogen to make amino
acids (used to build proteins & nucleic
acid) which combine to form DNA & RNA
-Nitrogen gas makes up 78% of Earth's
atmosphere
-Nitrogen fixation-process where bacteria
converts nitrogen gas into ammonia.