What are Protists?
Kingdom Protista is simple eukaryotes, neither animals nor plants nor fungi. Protists are unicellular in nature. It can be found that they are colonies of cells. Most biologists live in water, moist terrestrial environments, and even live in parasites.
The word “Protista” derived from the Greek word “protistos”, meaning “beginning”. These organisms are usually unicellular, and the cells of these organisms have nuclei attached to the organisms. Some of them also have structures such as flagella or cilia that contribute to the movement.
Scientists speculate that billions of years ago, these three states ran away from the ancestors of ordinary common creatures, so beings made connections between plants, animals, and fungi. Although the ancestors of this “protozoan” are fictional creatures, we can trace some of the genes found in modern animals and plants to these ancient creatures.
Therefore, these organisms are traditionally considered the first eukaryotic form of life and are precursors to plants, animals, and fungi.
Characteristics of Kingdom Protista
The main feature of all living things is that they are eukaryotes. This means that they have a core wrapped in a membrane. Other features of Kingdom Protista are:
- These are usually aquatic and are present in soil or wet areas.
- Most protists are single-celled organisms, but some are also multi-celled protists, such as kelp. Some kelp is very large, over 100 feet. (Giant Aeon).
- Like any other eukaryotes, cells of this species have nuclei and membrane-bound organs.
- They can be autotrophic or heterotrophic in nature. Autotrophs can make their own food and survive. On the other hand, heterotrophic organisms must obtain nutrients from other organisms such as plants or animals to survive.
- Symbiosis is seeing in such members. For example, kelp (seaweed) is a multicellular organism that provides protection for beaver from predators in thick kelp. In contrast, sea urchins often eat on kelp.
- Parasites have also been seen in protesters. Species such as protozoan trypanosomes can cause sleep sickness in humans.
- Proteases demonstrate movement through the cilia and flagella. Some organisms belonging to the Protista kingdom have pseudopods that may help them move.
- Protista breed asexually. Methods of sexual reproduction are extremely rare and occur only during periods of stress.
Classification of Protista
Kingdom Protista is divided into the following categories:
Protozoa are single-celled organisms. Historically, protozoa have been called “animal” protists because they are heterosexual and exhibit similar behavior to animals.
Parasitic protozoa are also present in cells of larger organisms. Most members have no predefined size. For example, the amoeba may change its shape indefinitely, but the paramecium has a fixed sleeper-like shape. The best-known examples of protozoa are amoeba, paramecium, sporangia, and euglena. Unlike other members of this group, Euglena is a free-living protozoon with chlorophyll. This means that it can cook on its own.
Protozoa can be divided into four categories:
Amoeboid protozoans: found mostly in water bodies, whether fresh or salt water. They suffer from pseudo foot (prosthetic leg), which can help them change their shape and hold and swallow food. For example, amoeba
Flagellated protozoans: as the name suggests, members of this group suffer from flagella. They can live independently or parasitically. Like euglena
Ciliated protozoans: They have cilia on their body, which helps in exercise and nutrition. They are always aquatic. Wg, Paramecium
Sporozoans: These organisms are so-called because they have a spore-like phase in their life cycle. For example, Plasmodium, Plasmodium.
Moulds are saprophytic organisms (they feed on dead and rotting materials). They are basically divided into two types. Clay mold and water mould. These are small organisms with many nuclei.
Typically, mold is characterized by the presence of spores, even visible to the naked eye.
This is another category of the Protista Empire. These are usually unicellular or multicellular organisms. They are photosynthetic and mainly present in freshwater sources or ocean lakes. They are characterized by a rigid cell wall.
Algae are divided into six species, namely, green algae, brown algae, red algae, diatoms, scorched plants, and eucalypts. Famous examples of algae are Volvox, Netrium, and Spirogyra, etc.