The Fungi (Second Edition)
Publisher Summary
This chapter provides an overview of fungi, which is similar to the cultivated mushroom, Agaricus bisporus, grown commercially on a very large scale and also survives in nature. The role of edible fruit bodies is the production of large numbers of spores that are borne on the gills below the cap, and the stalk raises fruit body above the ground to facilitate spore dispersal by air currents. The fruit body is composed of long, cylindrical branching threads known as hyphae and the spores are borne on specialized cells called basidia that may bear two or four spores. Hyphal growth is apical, wall extension being limited to roughly hemispherical apex of the hypha. Nutrients are absorbed from the substratum, and growth, nuclear division and hyphal branching occur to give circular colony that increases in diameter at a uniform rate. Plant diseases, such as rusts, smuts and mildews, are microscopic fungi responsible for attacking dead organic materials. Unicellular eukaryotes (protozoa and unicellular algae) were considered as a single kingdom, the Protista. The multicellular eukaryotes, were subdivided on the basis of nutrition into three kingdoms, photosynthetic plants (Plantae), absorptive fungi (Fungi), and ingestive animals (Animalia). Mycology, is the study of fungi. The fungi are simple eukaryotes that can be grown easily in pure culture, with high growth rates and in large amounts. The metabolic versatility of fungi is exploited by the fermentation, antibiotics, vaccines, medicine, agriculture and chemical industry.