Name: nancy n
Date: Around 1993
What is the most classic example of symbiosis?
Probably nitrogen-fixing bacteria on the roots of legumes (peas
and beans and alfalfa). The bacteria convert nitrogen into a chemical form
that the plant can use, the plant supplies the bacteria with sugar and other
nutrients. This is an example of "mutualism", in which both symbiont and host
benefit. The other 2 types of symbiosis are commensalism, in which the
symbiont benefits without affecting the host one way or the other, and
parasitism, in which the symbiont (the parasite in this case), benefits at the
expense of the host.
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Update: June 2012