Download Chapter 35 and 36 Notes

Chapter 35 & 36 Ecology
Population Density
•Population - members of the same species living in a specific _______________
•Population density - The number of individuals of a particular species divided by __________ or ___________.
•Ex: the number of fish per square kilometer of swamp.
•Pop. Density = ________________________
Population Density
•Example:
–What is the population density if there are 500 people in a 100km2 area? _______________________________
Niche
•Niche – An organisms unique living place defined by: __________, ______________, activity times, breeding, etc.
•A habitat is an organism’s ____________________________(biotic and abiotic).
•No two species can occupy the same _________________. But they can occupy the same ___________________
•Predation – one organism eats another.
•________________ are the organisms doing the eating.
•The organisms being eaten is the ______________
Symbiotic Relationships
•Symbiosis - A close interaction between two species. Ex: the clown fish and sea anemone.
Types of symbiotic relationships:
•____________________: 1 benefits, the other is harmed (tapeworm in intestinal tract)
•____________________:Both benefit. (Us and bacteria in our intestinal tract)
•____________________: 1 benefits, the other not affected (crab which uses seaweed for camouflage)
Disturbances in Communities
•Ecological succession: Process of community ____________________.
–Primary succession: a community arises out of a formerly _______________________ area (no soil).
•Example: New islands
•Secondary succession: a community changes after a dramatic ________________ in an area where there is soil.
Fire, volcano, clearing forest.
–Introduced species – humans move species from _________________ location to new areas they’re not native to.
•Ex: Kudzu.
Energy Flow
•How an organism ________________ determines the path of energy in the ecosystem.
–Producers (___________________): organism that makes if own _______________.
–Ex: Plants
–Consumers (_____________________): organisms that eat ______________________
–Ex: Animals, bacteria
Consumers may be:
–Herbivores: animals that eat plants
–Ex: ____________________
–Carnivores: animals that eat other animals
–Ex: ______________________
–Omnivores: eat plants and animals
–Ex: _______________________
–Decomposers: organism that breaks down organic waste
–Ex: _______________ and ____________________
Consumers
•Also categorized by their position in a particular food chain.
–___________________ consumer: when a consumer feeds directly on producers
–___________________ consumer: eat primary consumers
–Tertiary consumer: third level, eat secondary consumers
Trophic Levels
•Trophic level: feeding level in the ecosystem
•Food chain: the pathway of _____________ ___________ from one trophic level to another
•Food web: A pattern of feeding in an ecosystem consisting of interconnected and branching food ____________.
Energy Flows through Ecosystems
Ecological Energy Pyramids
•Illustrates how the energy transfers between trophic levels
–illustrates the ____________________________ at each trophic level.
–only ________________ of the energy of the previous trophic level is utilized by the next level
–90% is lost as ________________.
36.3 Nutrients Cycle through Ecosystems
•Carbon cycle
–During cellular respiration consumers break down _______________ and release _______________________ into
the atmosphere
–During photosynthesis producers take in ______________________ and form _______________________
Biological Magnification
•Pollutants become more and more ______________________ as they move up the food chain
–pollutants concentrate in the muscle, which is eaten. As organisms consume more and more contaminated
muscle, much pollutant accumulates in their tissues. Examples: __________ and _____________. P. 802
Threats to Biodiversity
•________________ ________________ is the number one threat to biodiversity
•Other threats to biodiversity
1. Introduced species (like Kudzu in Florida)
2. Overexploitation (killing elephants for ivory)
3. Pollution
Nutrients Cycle Through Ecosystems
• Carbon Cycle
-During _____________ _____________ consumers break down sugars and release carbon dioxide into the
atmosphere.
-During photosynthesis producers take in carbon dioxide and form sugars.
•
•
Water Cycle
1. ____________________- gaseous water becomes liquid water
2. ____________________-water exits the leaves
3. evaporation- liquid water becomes gas.
Nitrogen Cycle
-Relies heavily on __________________.
Human Impacts on the Environment
•Burning of fossil fuels effects:
- Greenhouse effect- carbon dioxide gets trapped in the atmosphere and causes the Earth to
____________ up.
- Caused by the destruction of the ozone layer by chlorofluorocarbons or ______________.
- In excess this can lead to global warming.