Download Ecology Notes - Harrison High School

Ecology Notes
I. Cycles of Matter Section 3-3 Pages 74-80
A. Recycling in the Biolsphere
1. Matter cycles through the biosphere because biological systems don’t use up
matter they transform it.
2. Matter becomes a part of living tissue and then leaves the body as waste
3. EX. Carbon atom in Carbon dioxide floats in the air and is absorbed by a
blueberry bush for photosynthesis. The Carbon dioxide is used to make food for
the plant. An animal eats the plant, the animal poops out the plant as waste.
B. The Water Cycle
1. All living things need water to survive
2. Water moves between the ocean the atmosphere and the land.
3. Evaporation: The process by which water changes from liquid form to an
atmospheric gas.
4. Transpiration: The process by which water evaporates form the leaves of
plants to an atmospheric gas.
5. Water cycle: The sun heats the atmosphere—warm moist air rises and cools—
water vapor condenses into tiny droplets that form clouds—droplets increase in
size until large enough to return to Earth’s surface as precipitation—rain taken
in by plant roots—cycle begins again.
6. Precipitation: rain, snow, sleet, hail
C. Nutrient Cycles: essential for ecosystems to keep functioning, prevent many
chemicals from reaching concentrations that would otherwise by toxic or harmful.
A. Three Types
1. Carbon Cycle: Carbon is present in the atmosphere as carbon dioxide. Carbon
dioxide gets there from volcanic activity, respiration, burning of fossil fuels by
humans, and the decaying of organic matter. Plants take in the carbon dioxide
for the building of carbohydrates during photosynthesis. The carbs. are passed
through food webs to animals and other consumers. They expel the carbon as
waste into the soil.
2. Nitrogen Cycle
a. Many different forms of nitrogen occur naturally in the biosphere.
b. Nitrogen gas makes up 78% of Earth’s atmosphere.
c. Ammonia, Nitrate (NO3), and Nitrite (NO2) are found in the wastes
produced by many organisms and in dead and decaying organic matter.
d. Only certain types of bacteria found in the soil and roots of plants,
called legumes can use atmospheric nitrogen.
e. The legumes carry out a process called Nitrogen fixation that takes
atmospheric nitrogen and changes into ammonia. Other bacteria in the
soil then change the ammonia into nitrates and nitrites which can be
taken in by plants to make proteins. Consumers then consume the
plants and use these same nitrates and nitrites to make proteins for
themselves.
f. When organisms die decomposers return nitrogen to the soil as
ammonia.
g. Once the ammonia is converted into nitrates, other soil bacteria
convert nitrates into nitrogen gas in a process called denitrification.
This process releases nitrogen into the atmosphere once again.
3. Phosphorus Cycle: Phosphorus is essential for forming part of DNA and RNA.
a. Phosphorus is found in rock and soil mernerals and in ocean sediments. As
the rock and sediment wear down, phosphate is released.
Ecological succession Section 4-1 Pages 94-97
Aquatic Ecosystems Section 4.4 Pages 106-112
Population Growth Sections 5.1 and 5.2 Pages 119-128
Humans in the Biosphere Chapter 6 pages 139-160