Studied by 10 people
Def: Species
A species is a group of living organisms that share common characteristics and can interbreed to produce fertile offspring.
Def: population
A population is a group of organisms of the same species that are living in the same area at the same time.
Def: Community
A group of populations living together and interacting with each other within a given area
Def: Habitat
A habitat is the natural environment where a particular plant or animal species lives and grows.
Def: Ecosystem
A community of living and non-living things that interact with each other
Includes plants, animals, microorganisms, soil, air, and water
Def: Autotrophs
synthesizes organic molecules from simple inorganic molecules
commonly referred to as producers
Def: Heterotrophs
obtains organic molecules from other organisms (either living/dead)
referred to as consumers
Def: Mixotrophs
certain unicellular organisms may on occasion use both forms of nutrition, depending on resource availability
Def: Consumers
ingest organic molecules from living/recently killed organisms
Def: Detritivores
ingest organic molecules found in the non-living remnants of organisms (e.g humus)
Def: Saprotrophs
release digestive enzymes and then absorb the external products of digestion
Def: Scavengers
type of consumer that principally feed on dead, decaying carcasses rather than hunting live prey
Why is the supply of inorganic nutrients on Earth finite?
nutrients are composed of elements (e.g carbon and oxygen)
the supply of such elements on earth is finite- new elements cannot be created
Explain nutrient recycling
autotrophs obtain inorganic nutrients from the air, water and soil, convert them into organic compounds
heterotrophs ingest these organic compounds, use them for growth and respiration, releasing inorganic byproducts
when organisms die, saprotrophs decompose the remains and free inorganic materials into the soil
the return of inorganic materials to the soil ensures the continual supply of raw materials for the autotrophs
What are the three main components required for a sustainable ecosystem?
energy availability → light from the sun provides the initial energy source for most communities
nutrient availability → saprotrophic decomposers ensure the constant recycling of inorganic nutrients within an environment
recycling of wastes → certain bacteria can detoxify harmful waste byproducts
Def: Mesocosm
enclosed environments that allow a small part of a natural environment to be observed under controlled conditions
Note 
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