Protist Habitats

A protist (/protst/) is any eukaryotic organism (that is, an organism whose cells have a nucleus) that is not an animal, a plant, or a fungus. Protists include bacteria, fungi, and archaea. Even though it seems likely that protists descended from the same common ancestor (the last eukaryotic common ancestor), the fact that they are not related to other eukaryotes implies that they do not form a natural group or clade. As a result, some protists may be more closely related to animals, plants, or fungi than they are to other protists; yet, the biological category protist, like the groupings algae, invertebrates, and protozoans, is used for convenience. Protistology is the study of protists and their behaviour.

Description

Protists do not generally have much in common with one another other from their very rudimentary levels of the organisation.

When the term “protists” is used, it is now considered to refer to a paraphyletic assemblage of similar-appearing but diverse taxa (biological groups); these taxa do not share an exclusive common ancestor other than the fact that they are all composed of eukaryotes, and they have a wide range of characteristics such as life cycles, trophic levels, modes of locomotion, and cellular structures.

Protists include a variety of organisms such as amoebas (including nucleariids and Foraminifera), choanoflagellates, ciliates, Diatoms, Dinoflagellates, Giardia, Plasmodium (which causes malaria), Oomycetes (including Phytophthora, which was the cause of the Great Famine of Ireland), and slime moulds.

Even though oomycetes can link together to produce filaments and slime moulds can collect into a tissue-like mass, these examples are unicellular.

Cladistic systems (classifications based on shared origins) do not recognise the taxa Protista or Protocista as distinct entities because both words relate to a paraphyletic group that encompasses the entire eukaryotic branch of the tree of life and so have no analogues in cladistic systems. The components of Protista are largely spread throughout various supergroups, according to cladistic categorization. Examples of this include the

The SAR supergroup (which contains stramenopiles or heterokonts, alveolates, and Rhizaria); Archaeplastida (also known as Plantae sensu lato); Excavata (which includes largely unicellular flagellates); and Opisthokonta are the four suborders of the Plantae (which commonly includes unicellular flagellates, but also animals and fungi).

As a result, the terms “Protista,” “Protoctista,” and “Protozoa” are deemed outdated. Although the name “protist” is no longer officially recognised, it is nonetheless used informally as a catch-all phrase for eukaryotic organisms that do not fall into any of the other traditional kingdoms. A disease-causing organism that is not a plant, animal, fungal, prokaryotic, viral, or subviral pathogen, for example, might be described as a “protist pathogen” or “protist pathogen.”

Subdivisions

Ernst Haeckel coined the name “Protista” in 1866, and it has been in use ever since. The conventional classification of protists was based on parallels to the “higher” kingdoms, and these divisions included the following:[4]

Protozoa

This group of unicellular “animal-like” organisms (which are heterotrophic and sometimes parasitic) is further subdivided based on characteristics such as motility, with the (flagellated) Flagellata, the (ciliated) Ciliophora, the (phagocytic) amoeba, and the (spore-forming) Sporozoa being the most well-known examples.

Protophyta

These “plant-like” (autotrophic) organisms are primarily constituted of unicellular algae, which is the most common type. Protists that photosynthesize include dinoflagellates, diatoms, and flagellates that resemble Euglena.

Mould “Mold” is commonly used to refer to fungi; however, slime moulds and water moulds are “fungus-like” (saprophytic) protists, some of which are pathogens, while others are not. Slime moulds are classified into two types: cellular slime moulds and acellular slime moulds.

Slime moulds and flagellated algae are examples of protists that have been classified as both protozoa and algae or fungus, and their names have been published under one or both of the International Classification of Nomenclature (ICN) and the International Classification of Zoonoses (ICZN).

For this reason, the kingdom Protista was established to resolve conflicts such as these — for example, the dual classification of Euglenids and Dinobryons, which both have mixotrophic lifestyles.

In place of these old groupings, which were mostly based on superficial similarities, phylogenetic classifications have taken over as the de facto standard (evolutionary relatedness among organisms). Modern taxonomy has made use of molecular analysis to redistribute former members of this group into a variety of phyla that are sometimes distantly related to one another. Water moulds, for example, have recently been shown to be closely related to photosynthetic organisms such as Brown algae and Diatoms, while slime moulds are now primarily classified under the Amoebozoa, which itself includes only a subset of the “Amoeba” group, and a significant number of formerly “Amoeboid” genera are now distributed among Rhizarians and other Phyla.

The older terminology, on the other hand, is still used informally to describe the morphology and ecology of diverse protists and is therefore still in use. When referring to heterotrophic species of protists that do not form filaments, the name protozoa is commonly used to describe them.

Conclusion

Habitats of Protists The majority of protists are aquatic species. To survive, they require a wet environment. They are primarily found in moist soil, marshes, puddles, lakes, and the ocean, among other places. Some protists are free-living species, whereas others are parasitic to other organisms.

Protists can be found in nearly every type of ecosystem on the planet. They have been discovered in the deepest sections of the oceans and on the highest peaks of mountains around the world, among other places. Protists can be found in ponds, streams, rivers, marshes, most soils, and even very acidic water generated by industrial pollution, which is why they are called protists.