Thus the relationship is primarily mutualistic. Ascomycetes A. Classification -Mycelium composed of septate hyphae with Woronin bodies . Septa have a central pore and a specialized structure called a Woronin Body that may act as a plug to seal off damaged hyphae. The algae provide the fungus with sugars from photosynthesis and the fungi provide the alga with a hospitable place to grow. In addition it is a widely studied model organism in molecular genetics and genetic engineering.
Many species form clamp connections when in the dikaryotic phase.
Unlike endomycorrhizae, these types do not penetrate the plant cells, but instead form a sheath around the outside of the root called a mantle . While the embedded images in this page are my own, the linked images are primarily borrowed from a web page created for a Oregon State University class on the fungi. This course is taught by Joey Spatafora and is referenced above.