Symbiosis

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Symbiosis Noun

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[sim-bee-oh-sis]

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Symbiosis

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A close and long-term interaction between two different biological species living in direct physical contact with each other.

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Example: This diagram explains symbiosis by showing its three main types: mutualism (both benefit), commensalism (one benefits, one is unaffected), and parasitism (one benefits, one is harmed).

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Mutualism Noun

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[myoo-choo-uh-liz-um]

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Mutualism

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A symbiotic relationship between two different species in which both organisms derive a mutual benefit from the interaction.

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Example: This diagram shows mutualism between ants and aphids; the ants protect the aphids, and in return, the aphids provide a sugary food source for the ants.

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Commensalism Noun

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[kuh-men-suh-liz-um]

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Commensalism

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A symbiotic relationship where one organism benefits while the other species is neither helped nor harmed by the interaction.

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Example: Barnacles attach to a whale's skin, gaining a safe place to live and access to food, while the whale is not significantly helped or harmed.

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Parasitism Noun

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[par-uh-si-tiz-um]

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Parasitism

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A symbiotic relationship where one organism, the parasite, benefits at the expense of the other organism, the host.

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Example: This diagram shows a host animal, the dog, and several examples of parasites, like fleas and ticks, that live on or in it to survive.

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Parasite Noun

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[par-uh-site]

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Parasite

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An organism that lives in or on another organism, its host, and benefits by deriving nutrients at the host's expense.

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Example: A tongue-eating louse, a type of parasite, is shown inside a fish's mouth, where it has replaced the fish's original tongue to survive.

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Host Noun

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[hohst]

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Host

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An organism that harbors a smaller organism or a parasite, providing nourishment and shelter for the guest organism.

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Example: This image shows a tick, a parasite, attached to the skin of an animal. The animal provides food and shelter for the tick, making it the host.

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Competition Noun

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[kom-pi-tish-un]

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Competition

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An interaction between organisms or species in which both are harmed by their shared need for a limited resource.

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Example: This image shows that competition happens when organisms fight for the same limited resources, either within their own species or with different species.

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Predation Noun

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[pri-day-shun]

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Predation

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A biological interaction where one organism, the predator, hunts, kills, and eats another organism, its prey.

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Example: A predator, the cheetah, hunts its prey, the springbok. This interaction, where one organism hunts and kills another for food, is called predation.

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Species Noun

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[spee-sheez]

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Species

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A group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding to produce fertile offspring.

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Example: This diagram shows that 'Species' is the most specific level in the hierarchy used by scientists to classify all living organisms.

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Lichen Noun

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[lai-kin]

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Lichen

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A composite organism that arises from algae or cyanobacteria living among filaments of fungi in a mutualistic relationship.

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Example: This diagram shows that a lichen is a single organism created from two different organisms, a fungus and an alga, living together in symbiosis.