Water Cycle
Water Cycle
• Transpiration: Excess water is evaporated off the leaves of plants.
• Evaporation: Water in oceans, lakes, and ponds changes from liquid
water into water vapor and is taken into the atmosphere.
• Condensation: Water vapor in the earth's atmosphere turns into
liquid water and a cloud is formed.
• Precipitation: The liquid water falls from the sky towards the earth
surface (could be rain, snow, hail. sleet, etc).
• Run off: Water runs towards rivers, lakes and oceans.
Carbon Cycle
Carbon Cycle
• Photosynthesis and Cell Respiration are the two key processes of
the carbon cycle. In photosynthesis, carbon atoms are transformed
from carbon dioxide into glucose. In cell respiration, carbon atoms
stored in glucose are transformed back into carbon dioxide and
released into the atomosphere. These transformations are made so
that energy can be transformed.
• Organic Carbon: Carbon atoms found in living or once-living
organisms.
• Mineral carbon: Carbon found in rocks or soil.
• Atmospheric CO2: Carbon dioxide found in the air.
Nitrogen
Cycle
• Plants and animals need nitrogen to grow. As shown in the pie
chart above, a large majority of Earth's atmosphere is made up of
atmospheric nitrogen (N2). However, this nitrogen is not usable to
plants. Plants are only able to use nitrogen in the form of
nitrate. Therefore, nitrogen must be "fixed," or transformed from
atmospheric nitrogen to usable nitrogen (nitrate). This is done by
bacteria in the soil.
Nitrogen Cycle
Phosphorus Cycle
• Phosphorus is an important element for all
forms of life. As phosphate (PO4), it makes up
an important part of the structural framework
that holds DNA and RNA together.
Phosphates are also a critical component of
ATP, the cellular energy carrier. Like calcium,
phosphorus is important to vertebrates; in the
human body, 80% of phosphorus is found in
teeth and bones.
Phosphorus Cycle
• The phosphorus cycle differs from the other major
biogeochemical cycles in that it does not include a gas
phase; although small amounts of phosphoric acid
(H3PO4) may make their way into the atmosphere,
contributing, in some cases, to acid rain. The water,
carbon, nitrogen and sulfur cycles all include at least
one phase in which the element is in its gaseous state.
Very little phosphorus circulates in the atmosphere
because at Earth's normal temperatures and pressures,
phosphorus and its various compounds are not gases.
The largest reservoir of phosphorus is in sedimentary
rock.
Phosphorus Cycle
• It is in these rocks where the phosphorus cycle begins.
When it rains, phosphates are removed from the rocks
(via weathering) and are distributed throughout both
soils and water.
• Plants take up the phosphate ions from the soil. The
phosphates then moves from plants to animals when
herbivores eat plants and carnivores eat plants or
herbivores.
• The phosphates absorbed by animal tissue through
consumption eventually returns to the soil through the
excretion of urine and feces, as well as from the final
decomposition of plants and animals after death..