Mycorrhizal fungi form symbiotic, mutually beneficial relationships with vascular plant roots. Mycorrhiza means "fungus roots" in Greek with the plural form being mycorrhizae or mycorrhizas. These fungi have been helping plants grow and thrive for eons. Mycorrhizal fungi attach themselves to plant roots and help the plant utilize organic material and water from the soil. The mycorrhizal fungi also form thin reinforcement filaments around the plant roots helping the plant to resist drought and transplant shock. Mycorrhizal fungi also elevate the plant's immune system by making it resistant to soil pathogens. As an added bonus the fungi also keep parasitic nematodes away. The plant pays for all of these benefits by providing the mycorrhizal fungi with food produced through the plant's photosynthesis.