Question

what is the meant by symbiosis

Answer 1

Close association or relationship between two or more living organisms, where at least one receives some sort of benefit from the relationship. Common examples in the animal kingdom include certain species of birds who eat parasites or bugs off the skin of elephants, and a bee which eats the nectar of flowers and in turn spreads the pollen which allows the flower to reproduce.

Answer 2

In a cleaning symbiosis, the clownfish feeds on small invertebrates that otherwise have potential to harm the sea anemone, and the fecal matter from the clownfish provides nutrients to the sea anemone. The clownfish is protected from predators by the anemone's stinging cells, to which the clownfish is immune. The clownfish emits a high pitched sound that deters butterfly fish, which would otherwise eat the anemone, making the relationship appear mutualistic.[1]

Symbiosis (from Greek συμβίωσις "living together", from σύν "together" and βίωσις "living")[2] is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasitic. The organisms, each termed a symbiont, may be of the same or of different species. In 1879, Heinrich Anton de Bary defined it as "the living together of unlike organisms". The term was subject to a century-long debate about whether it should specifically denote mutualism, as in lichens; biologists have now abandoned that restriction.