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Symbiosis PowerPoint Presentation

Symbiosis

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Symbiosis

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  1. Symbiosis Unit 1: Ecology and Sustainability of Ecosystems

  2. Symbiosis • Symbiosis refers to any close relationship between two different species. • Each species often develops specialized behaviors, life cycles, or structures.

  3. 1. Mutualism • When both species benefit from the relationship it is referred to as Mutualism. • Example: lichens provides a home for algae  algae produces food

  4. 2. Commensalism • Commensalism is when one specie benefits, and the other species is unaffected. • Ex: The relationship between barnacles and a grey whale. The barnacles feed passively from the water, and there is no effect on the grey whale.

  5. 2. Commensalism • Another example: Egrets (bird) and livestock  as cattle graze they walk around stir up insects in the grass making it available for the birds.  Cattle don’t notice.

  6. 3. Parasitism • Parasitism occurs when one organism lives and feeds on, or in, another organism called the host. The parasite benefits, and the host is harmed. • Example: The tapeworm is highly specialized to live in mammalian digestive systems. Tapeworms absorb nutrients from their host.

  7. 3. Parasitism • Scientists estimate that as many as 25% of all animal species may be parasites. • Positive role? They control population growth of species, preventing them from becoming too abundant. Parasites ensure the survival of the strongest members of a population.