Nutrient Cycles - Honors

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• Nutrient Cycles - Honors
• Water Cycle (pgs. 64 65)
• 1. Evaporation is the movement of water into the
  atmosphere as it changes from a liquid to a gas.
• 2. Transpiration is the evaporation of water
  from the leaves of plants, and plays an
  important role in plant circulation.
• 3. 70 of the Earth is covered by water.
• Water that evaporates from the Earths surface
  rises in columns of air warmed by sunlight. The
  water vapor cools as it rises and condenses into
  tiny droplets, forming clouds. Water returns to
  the Earths surface in the form of precipitation.
• 5. Precipitation is water on the earths surface
  in the form of rain, snow, sleet or hail. When
  precipitation falls on land, some of the water
  will flow into streams, lakes, rivers the
  ocean (bodies of water).

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6. Groundwater enters the plant through the
roots and re-enters the atmosphere through the
leaves (transpiration) 7. Water vapor can
remain in the atmosphere for up to 2 weeks. On
estimate, a water molecule that falls on land
may take 4000 years to complete the cycle! 8.
The sun is the source of energy that powers the
water cycle. 9. Diagram
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Carbon Cycle (pgs. 65 66) 1. 20 of the
Earths atmosphere is oxygen. 2. Young Earths
atmosphere was about 95 carbon dioxide. 3.
Today, Earths atmosphere is only 0.04 CO2 4.
The two main process involved in the carbon cycle
are photosynthesis and respiration. 5. The
formulas for photosynthesis and respiration are
the opposite each other. 6. Producers such as
green plants use carbon dioxide (CO2) water
(H2O) and sunlight to make their own food
(photosynthesis). When other organisms eat the
plants, CO2 and energy are released. 7.
Biological reactions in organisms are the main
part of the carbon cycle. This carbon cant be
used because it is already a part of a living
thing
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8. Two other important sources of carbon are the
ocean and rocks. When we burn fossil fuels,
some of the carbon stored in the bodies of the
dead organisms is released. 9. Most of earths
carbon is stored in rocks near the Earths
surface. 10. Diagram.
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Nitrogen Cycle (pgs. 66 67) 1. 78 of our
atmosphere is nitrogen. 2. Living things use
nitrogen to build amino acids the building
blocks of proteins and other body chemicals.
Most organisms cant use free N. 3.
Nitrogen-fixing bacteriafix or change free N to
useable compounds like ammonia, nitrates and
nitrites. Nitrogen-fixing bacteria live in the
soil and on the roots of legumes. 4. Legumes
are plants such as peanuts, beans and clover that
have nitrogen-fixing bacteria in nodules (little
lumps) on their roots. 5. Nitrates and nitrites
are compounds containing nitrogen and oxygen.
Nitrate is the most common source of nitrogen
for plants
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• 6. Nitrate is used in chemical fertilizers and
  also made through bacterial action.
• Decomposers return nitrogen to the soil in the
  form of ammonia to re-start the cycle.
• Diagram
• Nitrates are taken from the soil by plants. The
  plants then use the nitrogen in the nitrates to
  make proteins. These proteins are then used by
  the animals that eat the plants to get nitrogen
  for themselves.