Which type of fungi is single-celled and can be both harmful and helpful?

Yeasts are a type of fungi that are primarily single-celled organisms. They belong to the kingdom Fungi and are known for their versatility in various environments. Yeasts play a crucial role in many beneficial processes, such as fermentation, where they convert sugars into alcohol and carbon dioxide. This characteristic makes them invaluable in baking, brewing, and winemaking.

However, yeasts can also be harmful. Certain species, such as Candida albicans, can cause infections in humans, particularly in immunocompromised individuals or those with certain underlying health conditions. Therefore, yeasts embody the dual nature of being both beneficial and pathogenic, showcasing their importance in both ecological systems and human health.

In contrast, molds are multicellular fungi, viruses are non-living infectious agents that are not classified as fungi, and bacteria are prokaryotic microorganisms. This distinction highlights why yeasts are uniquely positioned as single-celled fungi that can have both positive and negative impacts.