Protistët

Protistët is a broad and diverse group of eukaryotic microorganisms. This means their cells contain a nucleus and other membrane-bound organelles, distinguishing them from prokaryotes like bacteria. Protists are not a single, unified kingdom in the way that plants, animals, or fungi are often considered. Instead, they represent a collection of organisms that do not fit neatly into these other categories. The definition of what constitutes a protist is largely based on exclusion, meaning they are eukaryotic organisms that are not plants, animals, or fungi.

This incredibly varied group includes single-celled organisms like amoebas, paramecia, and euglenas, as well as colonial and multicellular forms. Protists exhibit a wide range of lifestyles and ecological roles. Some are photosynthetic, like algae, producing their own food through sunlight and playing a vital role in aquatic ecosystems by generating oxygen and forming the base of food chains. Others are heterotrophic, meaning they obtain nutrients by consuming other organisms, acting as consumers or decomposers. Many protists are free-living, found in freshwater, saltwater, and moist terrestrial environments. However, some protists are parasitic, causing diseases in humans and other animals, such as malaria caused by Plasmodium falciparum, or in plants. Their reproduction can be asexual, through processes like binary fission, or sexual, involving genetic exchange. The study of protists is complex due to their vast diversity in form, function, and evolutionary history.