Читать книгу Antisepsis, Disinfection, and Sterilization - Gerald E. McDonnell - Страница 21

Protozoa represent one of the most abundant groups of life in the world. Over 60,000 species have been described, but estimates of the total variety that exist are much higher. They are single-celled eukaryotes, but unlike fungi, they lack a cell wall. They can be found in a variety of ecosystems, including water, soil, and as parasites in animals and plants. They are generally mobile and can be classified based on their respective modes of movement and microscopic morphologies (Table 1.6).

Similar to helminths, protozoa produce multiple forms during their respective life cycles, including oocysts and cysts that can survive for extended periods in the environment (Fig. 1.4). The amebas and flagellates mostly reproduce asexually, while the human-parasitic sporozoans are capable of both asexual and sexual reproduction.