Search results
Results from the WOW.Com Content Network
Pathogenic fungi are fungi that cause disease in humans or other organisms. Although fungi are eukaryotic , many pathogenic fungi are microorganisms . [ 1 ] Approximately 300 fungi are known to be pathogenic to humans; [ 2 ] their study is called " medical mycology ".
The English word fungus is directly adopted from the Latin fungus (mushroom), used in the writings of Horace and Pliny. [10] This in turn is derived from the Greek word sphongos (σφόγγος 'sponge'), which refers to the macroscopic structures and morphology of mushrooms and molds; [11] the root is also used in other languages, such as the German Schwamm ('sponge') and Schimmel ('mold').
The organisms that constitute the microbial world are characterized as either prokaryotes or eukaryotes; Eukaryotic microorganisms possess membrane-bound organelles and include fungi and protists, whereas prokaryotic organisms are conventionally classified as lacking membrane-bound organelles and include Bacteria and Archaea.
Pathogens include bacteria, fungi, protozoa, parasitic worms (helminths), and viruses. Each of these different types of organisms can then be further classified as a pathogen based on its mode of transmission. This includes the following: food borne, airborne, waterborne, blood-borne, and vector-borne.
But despite the development from two kingdoms to five among most scientists, some authors as late as 1975 continued to employ a traditional two-kingdom system of animals and plants, dividing the plant kingdom into subkingdoms Prokaryota (bacteria and cyanobacteria), Mycota (fungi and supposed relatives), and Chlorota (algae and land plants).
Bacteria and archaea are almost always microscopic, while a number of eukaryotes are also microscopic, including most protists, some fungi, as well as some micro-animals and plants. Viruses are generally regarded as not living and therefore not considered to be microorganisms, although a subfield of microbiology is virology , the study of viruses.
Gram-positive bacteria have a thick mesh-like cell wall made of peptidoglycan (50–90% of cell envelope), and as a result are stained purple by crystal violet, whereas gram-negative bacteria have a thinner layer (10% of cell envelope), so do not retain the purple stain and are counter-stained pink by safranin. There are four basic steps of the ...
The Fungi are classified as a kingdom that is separate from plants and animals. The discipline of biology devoted to the study of fungi is known as mycology or fungal biology, which is historically regarded as a branch of botany , even though genetic studies have shown that fungi are more closely related to animals than to plants.