The hallmark of Ascomycota is the ascus. An ascus is a microscopic, sac-like structure that typically contains eight ascospores. The cell walls of these fungi are primarily composed of chitin, providing structural support and protection. Additionally, they possess a unique septate hyphae structure, which is divided into individual cells by cross-walls called septa. These septa often have pores that allow for cytoplasmic streaming and communication between cells.
