2.2 Communities and Ecosystems Flashcards
Define Ecosystem
A community of interdependent organisms and their abiotic environment.
Define Community
A group of populations living and interacting in the same area.
Define Photosynthesis
The process by which green plants make their own food using water and carbon dioxide.
Define Respiration
The process in which food, often in the form of glucose, is broken down to release the energy it contains.
State the formula of Photosynthesis
Carbon Dioxide + Water –> Sugar + Oxygen
State the formula of Cellular Respiration
Glucose + Oxygen –> Carbon Dioxide + Water + ATP
Define a Producer
An organism that converts light energy into chemical energy. Examples include green plants, algae, etc.
Define Photo - Autotrophs
Make their own food from carbon dioxide and water using the energy from sunlight, ex. green plants.
Define Chemosynthetic Organisms
Make their own food from simple compounds and do not require sunlight; ex. bacteria in the deep ocean.
Define Consumer
An organism that feeds on other organisms. Includes herbivores, carnivores, and omnivores.
Define Decomposers
Organisms that feed on dead material and recycle nutrients in the ecosystem.
Define Biomass
The amount of biological matter in a living or recently living organism, measured in units of mass per unit area (e.g. gm^-2).
Define Trophic Level
The position that an organism occupies in a food chain as a result of its feeding habits. The term also defines the position of a group of organisms that feed at the same position in their food chain.
Define Ecological Pyramids
Graphical models of the quantitative differences between amounts of living material stored at each trophic level of a food chain. Are measured for a given area at a given time.
Define the Pyramid of Numbers
Shows the number of organisms at each trophic level in a food chain at one time. Units are number per unit area.
Define the Pyramid of Biomass
Contains the biomass (mass of each individual x number of individuals) at each trophic level. Biomass is the quantity of dry organic material at any level of ecological organization. Units are mass per unit area (g/m^2) or joules per unit area (J/m^2).
Define the Pyramid of Productivity
Shows the rate of flow energy or biomass through each trophic level. Shows energy / biomass being generated and available as food to the next trophic level during a fixed period of time.
Define Non - Biodegradable
Pollutants that cannot be broken down within an organism or trophic level.
Define Bioaccumulation
The build - up of a persistent pollutant within an organism or trophic level because it is not biodegradable.
Define Biomagnification
The increase in concentration of persistent pollutants along a food chain.
