Protozoihin

Protozoihin are a diverse group of single-celled eukaryotic organisms. The term "protozoa" itself is no longer a formally recognized taxonomic classification in modern biology but is historically used to describe these microscopic life forms. They are characterized by being heterotrophic, meaning they obtain nutrients by consuming other organisms, and by possessing a nucleus and other membrane-bound organelles within their single cell. Protozoihin inhabit a wide range of environments, including freshwater, saltwater, soil, and even the bodies of other organisms, where they can be free-living or parasitic.

Their motility varies; some protozoihin move using flagella (whip-like appendages), others use cilia (short, hair-like structures), and some employ pseudopods (temporary extensions of the cytoplasm). Reproduction in protozoihin can occur asexually, through processes like binary fission, or sexually. Many protozoihin play significant roles in ecosystems, such as nutrient cycling, and some are important to human health, either as pathogens causing diseases like malaria or amoebic dysentery, or as beneficial members of the gut microbiome. Their study is a crucial part of microbiology and parasitology.