What is a fungus? What effect does it have on human beings?

Single-celled or multicellular eukaryotes, which have cell walls, no chlorophyll, no roots and leaves, absorb nutrients by saprophytic or parasitic means and reproduce with spores. Fungi actively participate in the mineralization of soil organic matter and the formation of humus colonization, which is an essential transformation factor of soil fertility and an important part of natural material cycle. Fungi are widely used in brewing and fermentation industries to produce wine, sauce and tofu, as well as antibiotics, organic acids, enzyme preparations, vitamins and steroid hormones. In agricultural production, it is used as feed starter, additive, plant growth hormone and pesticide, and forms mycorrhiza with plants to absorb mineral nutrients. Fungi are also pathogens of animal and plant diseases, which cause mildew and deterioration of grain and agricultural and sideline products during storage and transportation, and also cause mildew of clothes, equipment, tools, instruments and industrial raw materials. Fungi can also produce toxic substances, which seriously threaten human and animal health.