Fungi, like ascomycetes, grow through a network of filament type structures called hypha. They are the main vegetative growth of a fungus, and large networks of hyphae (plural form) are called a mycelium. There are two main classifications of hyphae based on the type of cell division, septate or aseptate. Septate hyphae have divisions between the growing cells called septa that are internal cell walls that are perforated to allow organelles and cytoplasm to pass through. Aseptate are also called coenocytic hyphae and are multinucleated, meaning that they lack septa. In other words, the cells are essentially supercells with multiple nuclei and sets of organelles within a single very large cell. This results from cells undergoing multiple cycles of cell division like mitosis without cyctokinesis (separation) following them. One benefit to having coenocytic hyphae is structural strength. Skeletal type hyphae are long with lots of branching to provide structural support for the fungus. Coenocytic hyphae help make up these type of cells structures.