Search results
Results from the WOW.Com Content Network
A protist (/ ˈ p r oʊ t ɪ s t / PROH-tist) or protoctist is any eukaryotic organism that is not an animal, land plant, or fungus.Protists do not form a natural group, or clade, but are a polyphyletic grouping of several independent clades that evolved from the last eukaryotic common ancestor.
The history of the study of protists has its origins in the 17th century.Since the beginning, the study of protists has been intimately linked to developments in microscopy, which have allowed important advances in the understanding of these organisms due to their generally microscopic nature.
Marine protists are defined by their habitat as protists that live in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. Life originated as marine single-celled prokaryotes (bacteria and archaea) and later evolved into more complex eukaryotes .
Protists are distributed across all major groups of eukaryotes, including those that contain multicellular algae, green plants, animals, and fungi. If photosynthetic and fungal protists are distinguished from protozoa, they appear as shown in the phylogenetic tree of eukaryotic groups.
It contains a variety of free-living and symbiotic protists, and includes some important parasites of humans such as Giardia and Trichomonas. [5] Excavates were formerly considered to be included in the now obsolete Protista kingdom. [6]
Protists are the eukaryotes that cannot be classified as plants, fungi or animals. They are mostly unicellular and microscopic.Many unicellular protists, particularly protozoans, are motile and can generate movement using flagella, cilia or pseudopods.
Get answers to your AOL Mail, login, Desktop Gold, AOL app, password and subscription questions. Find the support options to contact customer care by email, chat, or phone number.
Autotrophic protists that make their own food without needing to consume other organisms, usually by using photosynthesis Red algae, Cyanidium sp. Green algae, brown algae, diatoms and some dinoflagellates. Plant-like protists are important components of phytoplankton discussed below. Animal-like