Download Essential terms to know in Ecology

Essential terms to know in Ecology
Habitat: The place where an organism lives. The habitat of the jaguar is the forests of South and
Central America.
Species: A group of organisms that can interbreed and produce fertile offspring. All dogs belong to
the same species because you can mate any two dogs together and they will produce offspring that
are fertile. Horses and donkeys can breed together to produce a mule, BUT they are not the same
species because mules are infertile (they cannot reproduce).
Population: A group of organisms of the same species living in the same place at the same time.
The population of humans (same species) in Mexico City (same place) today (same time) is 24
million.
Community: A group of populations living and interacting together in a particular place. The
community of organisms in a rain forest includes trees, small plants, insects, birds, reptiles, monkeys
and predators like the jaguar.
Ecosystem: An ecosystem includes all of the living things in a given area interacting with each other
(biotic) and with their non-living environments (abiotic).
Abiotic: The physical non living factors that can affect the number and type of organisms within an
ecosystem. Abiotic factors include temperature, water, oxygen levels, amount of light, soil type,
water pH, salt levels and availability of nutrients.
Biotic: The living factors that affect the number and type of organisms within an ecosystem. Biotic
factors include food supply and numbers of predators.
Ecology: The study of how living organisms interact with each other and with their environment.
Autotrophs: Organisms that can make their own food from inorganic chemicals. Plants are
autotrophs because they can make their own food (glucose) for simple inorganic molecules (carbon
dioxide and water).
Heterotrophs: Organisms that cannot make their own food from simple inorganic molecules. They
must eat autotrophs or eat other heterotrophs. Humans are heterotrophs.
There are three types of heterotroph: consumers, detritivores, saprotrophs
Consumers: Organisms that get their food by eating other living organisms or by eating organisms
that were alive recently. Humans are consumers.
Detritivores: Organisms that eat non living organic matter such as faeces, dead leaves, carcasses of
dead animals. Detritivores have a digestive system that digests organic matter inside the organism.
Earthworms, woodlice and dung beetles are all detritivores.
Saprotrophs: These organisms do not eat non living organic matter. Instead they secrete enzymes
onto the organic matter. The enzymes digest the organic matter and then the saprotroph absorbs
the digested nutrients. Saprotrophs have no digestive system; their food is digested outside their
body. Bacteria and fungi are saprotrophs. Decomposers are saprotrophs.
Biodegradable: Capable of being broken down by natural biological processes; i.e. the activities of
decomposer organisms. Examples of biodegradable items include paper, wood and plant material.
Biodiversity: The amount of biological or living diversity in an area. It includes the concepts of
species diversity, habitat diversity and genetic diversity.
Biome: A collection of ecosystems sharing a similar climate; i.e. tundra, tropical rainforest, desert.
Biosphere: That part of the Earth inhabited by organisms, that is, the narrow zone (a few km thick)
in which plants and animals exist. It extends from the upper part of the atmosphere (where birds,
insects and wind-blown pollen may be found) down to the deepest part of the Earth's crust to which
living organisms venture, including the bottom of the ocean.
Competition: When 2 or more organisms need a limited supply of a resource; i.e. food, water, light,
space, mates, nesting sites. Competition can be between organisms of the same species or between
different species.
Global Warming: An increase in average temperature of the Earth's atmosphere.
Greenhouse Gases: Those atmospheric gases which absorb infrared radiation, causing world
temperatures to be warmer than they would otherwise be. Greenhouse gases include methane and
carbon dioxide.
Niche: A species' share of a habitat and the resources in it. Depends on where the specie lives and
what it does. The niche includes the habitat, how the organism gets food and its relationships with
other organisms. Two species with a similar niche will compete but both may exist. Where two
species have the same niche they will compete and one species will be the loser and have to leave
the niche.
Essential terms to know related to Food Webs
Food Chain: A series of organisms showing their feeding relationships.
Producer: The first organism in a food chain. Producers are autotrophs.
Primary Consumer: The organism in a food chain that uses the producer for food.
Top Consumer: The final organism in a food chain.
Food Web: A community of organisms with interrelated food chains at various levels.
Trophic Level: The position of an organism in a food chain. The producer is the first trophic level,
the primary consumer is the second, etc.
Biomass: The total dry mass of organic matter in an organism.
Biomagnification: Chemical substances become more concentrated in organisms as the trophic
levels increase.
Herbivore: A consumer that only eats plants.
Carnivore: A consumer that only eats meat.
Omnivore: A consumer that eats both plants and meat.
Predation: An interaction between organisms in which one organism (the predator) captures
another and feeds on the captured organism (the prey).
Parasitism: An interaction between organisms where one organism (the parasite) lives on or in
another organism (the host) and uses the organism for food, protection and gives no benefit to the
host organism. Examples of human parasites are tapeworms and lice. All viruses are parasites.
Mutualism: An interaction between organisms where both organisms benefit from the presence of
the other. A good example is a lichen. A lichen is a fungus and an algae living together in a mutual
relationship. The algae photosynthesise and provide food for the algae. In return, the fungus
prevent the algae from drying out and helps provide minerals to the algae.
ECOLOGY TERMS TEST
1. A lichen is a mutual relationship between two organisms: a fungus and an ……………..
2. An organism that only eats meat ……………………………….
3. The total dry mass of organic matter is the …………………………..
4. An increase in the average temperature of the atmosphere …………………………………………..
5. The study of how living organisms interact with each other and their environment ……………..
6. The final organism in a food chain …………………………………..
7. The first organism in a food chain …………………………..
8.
A group of organisms of the same species living in the same place at the same time …………………
9. Organisms that secrete digestive enzymes onto dead organic matter ………………………………
10. Areas in the same biome share a similar ……………………………
11. The trophic level of the primary consumer in a food chain …………………………………….
12. Methane and carbon dioxide are examples of …………………………………………. gases
13. Three abiotic factors that can affect the number and type of organisms in an ecosystem
………………………………………………………………………………………………………………………………………..
14. Organisms that cannot make their own food from simple organic molecules …………………..
15. Dogs and wolves belong to the same …………………………. because they can reproduce together to
produce fertile offspring.
16. Organisms that eat non-living organic matter …………………………………….
17. A group of populations living and interacting in a particular place …………………………………
18. The part of the earth where life can exist ………………………………………
19. The living diversity within an area ………………………………………..
20. The place where an organism lives ……………………………………….