An ecosystem includes living organisms and the nonliving surroundings with which they interact. This lesson introduces the levels of ecological organization, the resources organisms compete for, and the major categories of ecosystems.
A community is all the living organisms within a particular habitat. Organisms in a community may compete with members of their own species or with members of other species. Competition occurs when organisms require the same limited resources.
All flashcards
How do a community and an ecosystem differ?
A community includes living organisms in a habitat; an ecosystem also includes their interactions with the abiotic environment.
What resources can organisms compete for?
Limited resources such as organic material, sunlight, and mineral nutrients.
What are the three broad categories of ecosystems?
Freshwater, ocean, and terrestrial ecosystems.
What is a holistic ecosystem study?
A study that attempts to quantify an entire ecosystem’s composition, interactions, and dynamics.
How can evolution affect an ecosystem?
Evolved differences among organisms can alter environmental conditions and affect other species.
Quiz questions
Why does energy availability limit the number of trophic levels in a food chain?Answer: Less energy is available at each successive trophic level.
What is a mesocosm in ecological research?Answer: A partitioned part of a natural ecosystem used for experiments.
What does equilibrium mean in an ecosystem?Answer: Organisms are in balance with one another and their environment.
Where does a grazing food web begin?Answer: With living photosynthetic organisms.
How can combining controlled experiments with holistic ecosystem studies improve ecological research?Answer: It combines experimental control with evidence from natural systems.
Based on Biology 2e by Mary Ann Clark, Matthew Douglas, Jung Choi (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.