Give examples of mutually beneficial relationships of organisms?

Relations between flowering plants and insects – pollinators – butterflies, bees, bumblebees, ghost flies. They visit flowers to enjoy nectar, and for plants this is a special device for attracting insects – the allocation of sweet juice by nectaries. Flying from flower to flower, insects carry pollen, providing pollination of plants.
Many species of ants willingly absorb aphid honey dew, the sweetish liquid that these insects secrete, as an additional food. Ants can be said to graze aphids – they transfer them from one plant to another, thereby providing food (young leaves), protect them from predatory insects. This is a mutual benefit from such relationships for a population of ants and aphids.
Most plants and fungi form mycorrhiza. The strings of the fungus braid the roots and thereby greatly increase the suction surface of the root system.

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