Mycorrhizal fungi live in the soil and interact with the roots of plants. Essentail nutrients (e.g. nitrogenous compounds) are taken from the soil by the fungi and transferred to the plant roots. The...

Mycorrhizal fungi live in the soil and interact with the roots of plants.  Essentail nutrients (e.g. nitrogenous compounds) are taken from the soil by the fungi and transferred to the plant roots.  The fungi extract carbohydrates from the plant roots.  What type of interaction is occurring?