Introduction to Ecology Chapter 3 The Biosphere What
Introduction to Ecology Chapter 3: The Biosphere
What is Ecology? ecology- study of interactions among organisms and between organisms and their physical environment Ecological studies focus on different levels of organization: Species- group of similar organisms, breed producing fertile offspring Population – group of individuals of same species living in same area Community – different populations living in same area Ecosystem- all organisms living together in a place with their environment Biome- group of ecosystems with similar climates and typical organisms Biosphere- entire planet
Factors in the Environment biotic factors- any living part of an ecosystem e. g. animals, bacteria, fungi, plants abiotic factors- any nonliving part of the environment e. g. sunlight, heat, precipitation, soil type, wind Interaction between these two factors vital for ecosystem to thrive
Energy, Producers, and Consumers All organisms have a need for energy for life functions Where does it come from? The sun Energy cannot be created but used from other sources Who gets the energy from the sun? Autotrophs AKA- primary producers- first producers of energy-rich compounds that are later used by other organisms
Energy, Producers, and Consumers Chemoautotrophs- use chemical energy to produce carbs Live in EXTREME environments with no light Consumers- aka heterotrophs Rely on other organisms for energy and nutrients Classified by ways in which they acquire food and nutrients
Types of Consumers Herbivores Primary consumers consume primary producers (plants) Cows, deer, caterpillars Carnivores Secondary & tertiary consumers kill and eat other animals Snakes, foxes, birds of prey Omnivores Secondary consumers eat both plant and animals Humans, bears, raccoons
When organisms die, they leave energy & matter in remains Decomposers- break down remains/waste into inorganic molecules in the soil Producers can use these molecules to make organic compounds Essential to every ecosystem Classified by type of organic matter they break down: Scavengers- consume soft tissue of dead animals (vultures, raccoons, blowflies) Detritivores- consume detritus (dead leaves, feces, organic debris collected on soil or bottom of body of water). Include earthworms, millipedes, dung beetles, “bottom feeders” (sea cucumbers & catfish) Saprotrophs- final step in decomposition, feed on remaining organic matter left after other decomposers work (fungi, bacteria, single-celled protozoa). Only fungi can decompose wood.
- Slides: 7