1. Plant & Animal Interdependency
Living Environment
Key Idea 6.1

2. Key Idea 6
Plants and animals depend on each other and their physical environment.
Interactions of organisms and their environment result in the flow of energy and a cycling of materials that are essential for life.
Competition may be for nonliving resources, or for living resources among different species or among the same species.
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3. Key Idea 6 – Major Understandings
Energy flows through the ecosystem, from Sun through photosynthetic organisms to herbivores, carnivores, and decomposers
Relationships between organisms may be competitive or beneficial
Biosphere is recycled by Earth processes
Biodiversity increases the stability of the ecosystem
Chemical elements pass through food webs as illustrated in the pyramid of energy
Biodiversity ensures a variety of genetic material, which in turn increases chances for survival
Carrying capacity is limited by available energy, water, oxygen, minerals and recycling
Interrelationships and interdependencies affect the development of stable ecosystems
Competition exists for resources such as food, space, water, air and shelter
Environmental alteration comes from both natural and human made changes
Ecosystems are dependent on physical conditions including light, pH, temperature, soil/rock type
Altered ecosystems may last for thousands of years
Environments and resources are finite
Damaged ecosystems will likely recover in states to stability
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4. Performance Indicator 6.1
Performance Indicator 6.1 Explain factors that limit growth of individuals and populations.
Abiotic factors: nonliving
Biotic factors: living
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5. Abiotic Factors Abiotic Factors (nonliving): Intensity of light
Range of temperatures
Amount of moisture (H2O)
Type of substratum such as soil and rock
Availability of inorganic substances such as common salts (NaCl)
Supply of gases such as oxygen (O2), carbon dioxide, (CO2), and nitrogen (N2).
pH (such as the acidity or alkalinity of the air, water and soil.
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6. Limiting Factor
Limiting Factor - the necessary resource that an organism needs that there is the least of.
Determines the type of organisms that may exist in that environment.
Some plants live well on a forest floor under tall trees, but will not do well in an open field due to increased light.
The low annual temperature common to the northern latitudes determines in part what plants can exist there, because some plant enzymes work better at higher temperatures.
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7. Limiting Factors (cont)
If a body of water’s dissolved oxygen level is low, fish that need higher oxygen levels could suffocate and die.
The salt-laden air and water of coastal areas limit what species can exist in those regions. Some species of fish, shellfish, and other marine species could die in freshwater due to an imbalance of water pressure in their tissue.
Because of low pH caused by acid rain, more than 200 lakes in the Adirondacks (NY) have virtually no life in them.
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8. Material Cycles
Process of moving and cycling materials through the environment.
Oxygen Cycle
Carbon Cycle
Water Cycle
Nitrogen Cycle
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9. Oxygen Cycle Diagram
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10. Carbon Cycle Diagram
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11. Water Cycle The Water Cycle Terms: Evaporation Transpiration
Condensation
Precipitation
Runoff, groundwater, seepage
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12. Water Cycle Diagram
Energy From Sun
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13. Nitrogen Cycle
The nitrogen cycle: Recycle the nitrogen that is necessary for the production of proteins.
Atmospheric nitrogen is converted into nitrates by nitrogen fixing bacteria.
Plants use nitrates for protein synthesis.
Animals which eat plants convert the plant protein into animal protein.
Nitrogenous waste and the bodies of dead plants and animals are broken down by decomposers (bacteria of decomposition) and ammonia is released.
Ammonia may be converted into nitrates by nitrifying bacteria.
Nitrogen containing compounds may be broken down by denitrifying bacteria, resulting in the release of nitrogen in the atmosphere.
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14. Nitrogen Cycle Diagram
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15. Energy Flow & Nutritional Relationships
Energy Flow: Green plants convert radiant energy from the sun into chemical energy.
A food chain involves the transfer of energy from plants through a series of organisms.
Producers
a. make their own food (autotrophs)
plants & algae's (photosynthesis)
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16. Consumers & Decomposers
can’t make own food (heterotrophs)
herbivores: plant eaters (primary consumers)
carnivores: meat eaters
predators: kill own food (prey)
scavengers: eat animals they don’t kill
omnivores: eat both plants and animals
Decomposers: Bacteria & fungi that break down dead bodies and wastes products. They recycle nutrients.
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17. Food Chain Food Chains and Food Webs:
Food Chain: sequence of organisms through which food passes in a community.
Algae Insect Fish Man
Producer 10 Consumer 2nd Consumer Third Level
Arrows point in direction of the flow of energy!
Food Web: Different food chains in an area which are interrelated to form a food network.
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18. Food Chain Diagram
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19. Food Web Diagram
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20. Energy Pyramid Pyramids of Energy and Biomass
All energy on the earth ultimately comes from sun !
Energy is lost at each link of the food chain.
lost as heat
approximately 10% of food energy in a given level will become incorporated in the bodies of organisms in the next higher level.
as you go up a food chain or pyramid the number of organisms decrease and the size increases. Biomass decreases.
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21. Energy Pyramid Diagram
Pyramid of Energy
killer whales
Final
Consumers
Decrease in Biomass
seals
Tertiary Consumers
Secondary Consumers
fish
Primary Consumers
zooplankton
phytoplankton
plants
Producers
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22. Nutritional & Symbiotic Relationships
Homeostasis of an ecosystem:
Ex. If a rabbit population in a community decreases there will be less food available for foxes. This causes a decrease in the number of foxes. With fewer foxes, the rabbit population will increase.
Base line
Foxes
Rabbits
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23. Symbiotic Relationships
+ = benefit to, - = expense of, 0 = not affected
Symbiosis: When two species of organisms interact with each other in any way.
Mutualism: Symbiotic relationship in which both species benefit. (+,+)
termites & protozoa
lichens (algae & fungi)
cows and bacteria
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24. Symbiotic Relationships (cont)
Commensalism: Symbiotic relationship in which one of the organisms benefit and the other is not affected. (+,0)
Remoras & Sharks
Parasitism: Symbiotic relationship between parasites and host. (+,-)
tape worm & dog, fleas and dogs, human and viruses
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25. Predator and Prey
Predation: Feeding relationship between predators and prey.
predator attacks organism for food
prey is the animal that serves as food
if the predator - prey relationship is in balance, both benefit as a species but not as individuals.
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26. Competition in an Ecosystem
Competition in Ecosystems:
Competition: rivalry between individuals for a specific resource.
Intraspecific Competition: between members of same species.
Interspecific Competition: Competition between members of different species.
Competition can be for things like:
Habitat: Where an organism lives.
Niche: The role of the organism in the ecosystem.
Light, food, nesting areas, space, water, mates etc...
Limiting Factor: the necessary resource that an organism needs that there is the least of.
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