The orchid is that the plant compensates for its lack of a true water-retentive root system by working with a certain type of fungi called mycorrhizae fungi during some portion of their life cycle. During this period, the fungi grow partly inside orchid roots, helping the plant to absorb water and minerals. The orchid "repays" the fungi by producing some nutrients during photosynthesis that help the fungi to survive. This kind of relationship, where two organisms help one another, is called a symbiotic relationship.