Botany, plant science(s), or plant biology (from Ancient Greekβοτάνηbotane, "pasture, grass, or fodder" and that from βόσκεινboskein, "to feed or to graze"), is a discipline of biology and the science of plantlife. Traditionally, the science included the study of fungi, algae, and viruses. A person engaged in the study of botany is called a botanist.
Botany covers a wide range of scientific disciplines including structure, growth, reproduction, metabolism, development, diseases, chemical properties, and evolutionary relationships among taxonomic groups. Botany began with early human efforts to identify edible, medicinal and poisonous plants, making it one of the oldest branches of science. Nowadays, botanists study about 400,000 species of living organisms.
The beginnings of modern-style classification systems can be traced to the 1500s–1600s when several attempts were made to scientifically classify plants. In the 19th and 20th centuries, major new techniques were developed for studying plants, including microscopy, chromosome counting, and analysis of plant chemistry. In the last two decades of the 20th century, DNA was used to more accurately classify plants.
A mushroom (or toadstool) is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi (Basidiomycota, Agaricomycetes) that have a stem (stipe), a cap (pileus), and gills (lamellae, sing. lamella) or pores on the underside of the cap.
"Mushroom" describes a variety of gilled fungi, with or without stems, and the term is used even more generally, to describe both the fleshy fruiting bodies of some Ascomycota and the woody or leathery fruiting bodies of some Basidiomycota, depending upon the context of the word.
Forms deviating from the standard morphology usually have more specific names, such as "puffball", "stinkhorn", and "morel", and gilled mushrooms themselves are often called "agarics" in reference to their similarity to Agaricus or their place Agaricales. By extension, the term "mushroom" can also designate the entire fungus when in culture; the thallus (called a mycelium) of species forming the fruiting bodies called mushrooms; or the species itself.