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Bio-ch.3
Ecology
| Question | Answer |
|---|---|
| scientific study of interactions among organisms and between organisms and their environment | ecology |
| contains all the combined portions of the planet in which all of life exists, including land, water and air (atmosphere) | biosphere |
| to understand __________ within the biosphere, ecologists ask questions about events and organisms that range in complexity from a single individual to the entire _________ | relationships, biosphere |
| a group of organisms so similar to one another they can breed and reproduce fertile offspring | species |
| group of individuals that belong to the same species and live ing the same area | population |
| different populations living together in the same area | community |
| group of ecosystems that have the same climate and similar dominant communities | biome |
| regardless of the tools they use, scientists conduct modern ecological research using three basic approaches: ________, __________, and________ | observing, experimenting, and modeling |
| _______ is the main energy source for life on earth | sunlight |
| some types of organisms rely of the ________ stored in inorganic chemical compounds | energy |
| plants, some algae, and certain bacteria that can capture energy from the sunlight or chemicals and use that energy to produce food | autotrophs |
| autotrophs are also called________ | producers |
| kelp is an autotroph that uses energy from the sun to produce ________ _________ | living tissue |
| when organisms use chemical energy to produce carbohydrates | chemosynthesis |
| organisms that rely on other organisms for their energy and food supply | heterotrophs |
| heterotroph are also called ________ | consumers |
| when plants take in water and carbon dioxide, and release oxygen into the air. THe sun is the energy source, carbohydrates (sugar) is what the plant makes for its food | photosynthesis |
| obtain energy by eating plants | herbivores |
| eat animals | carnivores |
| eat both plants and animals | omnivores |
| feed of plant and animal remains and other dead matter | detritivores |
| break down organic matter | decomposers |
| produce energy from chemicals | chemotrophs |
| Energy flows through an ecosystem in one direction, from the ______ or inorganic compounds, to _______ (producers) then to various ___________ (consumers) | sun, autotrophs, heterotrophs |
| series of steps, organisms transfer energy by eating and being eaten | food chain |
| _______ _______ show the one way flow of energy in an ecosystem | food chains |
| links all the food chains of an ecosystem together | food web |
| each step in a food chain or food web is called this | trophic level |
| diagram showing relative amounts of energy or matter contained within each trophic level in a food chain or food web | ecological pyramid |
| only about what percent of the energy available within one trophic level is transferred to organisms at the next trophic level | 10% |
| the total amount of living tissue within a given trophic level is called _____ | biomass |
| true/false: because only ten percent of energy in one trophic level is available in the next, each higher trophic level can support only about 1/10th the amount of living tissue | true |
| unlike the one way flow of energy, ______ is recycled within and between ecosystems | matter |
| elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another through _____________ cycles | biogeochemical |
| when water changes from a liquid to a gas | evaporation |
| water enters the atmosphere by evaporating from the leaves of plants | transpiration |
| gaseous water changing into a liquid | condensation |
| water on the ground running off into lakes, streams,or oceans | runoff |
| water percolating into the ground | seepage |
| all the chemical substances an organism needs to survive are called ________ | nutrients |
| every living organism needs ________ to grow and carry out essential life functions | nutrients |
| t/f like water, nutrients are passed between organisms and the environment through biogeochemical cycles | true |
| ________ is the key ingredient in all living organisms | carbon |
| the process by which bacteria convert nitrogen gas into ammonia | nitrogen fixation |
| other soil bacteria convert nitrates into nitrogen gas in a process called | denitrification |
| true/false phosphorous is abundant in the biosphere | false |
| true/false phosphorous is essential to living organisms because it forms important life sustaining molecules such as RNA and DNA | true |
| true/false biological processes like photosynthesis are involved in the carbon cycle | true |
| all organisms require ______ to make amino acids which are used to build proteins | nitrogen |
| true/false many forms of nitrogen occur naturally in the biosphere | true |
| rate at which organic matter is created by producers | primary productivity |
| when an ecosystem is limited by a single nutrient that is scarce or cycles very slowly | limiting nutrient |
| when an aquatic ecosystem recieves a large input of a limiting nutrient, the result is an immediate increase in the amount of algae and other producers,called an _____ ______ | algal bloom |