Search results
Results from the WOW.Com Content Network
Protists reproduce asexually or sexually. If the protists reproduce asexually, they do so through binary fission, multiple fission, budding, and fragmentation. If the protists reproduce sexually, they do so through a syngamy process where there is a fusion of the gametes. If this occurs in an individual it is recognized as autogamy.
For example, the human body louse transmits the bacterium Rickettsia prowazekii which causes epidemic typhus. Although invertebrate-transmitted diseases pose a particular threat on the continents of Africa, Asia and South America, there is one way of controlling invertebrate-borne diseases, which is by controlling the invertebrate vector.
Some protists are significant parasites of animals (e.g.; five species of the parasitic genus Plasmodium cause malaria in humans and many others cause similar diseases in other vertebrates), plants [179] [180] (the oomycete Phytophthora infestans causes late blight in potatoes) [181] or even of other protists.
The term continues to be used in a loose way to describe single-celled protists (that is, eukaryotes that are not animals, plants, or fungi) that feed by heterotrophy. [9] Traditional textbook examples of protozoa are Amoeba, Paramecium, Euglena and Trypanosoma. [10]
Kinetoplastida (or Kinetoplastea, as a class) is a group of flagellated protists belonging to the phylum Euglenozoa, [3] [4] and characterised by the presence of a distinctive organelle called the kinetoplast (hence the name), a granule containing a large mass of DNA.
Amoebozoa are a group of motile amoeboid protists, members of this group move or feed by means of temporary projections, called pseudopods. The best known member of this group is the slime mold, which has been studied for centuries; other members include the Archamoebae, Tubulinea and Flabellinia. Some Amoeboza cause disease.
Protists are highly diverse organisms currently organised into 18 phyla, but are not easy to classify. [89] [90] Studies have shown high protist diversity exists in oceans, deep sea-vents and river sediments, suggesting a large number of eukaryotic microbial communities have yet to be discovered.
A parasitic disease, also known as parasitosis, is an infectious disease caused by parasites. [1] Parasites are organisms which derive sustenance from its host while causing it harm. [ 2 ] The study of parasites and parasitic diseases is known as parasitology . [ 3 ]