Protozoa (sg.: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris.

Protozoa are microscopic unicellular eukaryotes that have a relatively complex internal structure and carry out complex metabolic activities. Some protozoa have structures for propulsion or other types of movement. On the basis of light and electron microscopic morphology, the protozoa are currently classified into six phyla.

2023年8月3日 · Protozoa are unicellular eukaryotic microorganisms having a membrane-bound nucleus and other organelles within their cells. Despite their small size, they are incredibly diverse and exist in various aquatic and terrestrial environments worldwide.

2025年1月17日 · protozoan, organism, usually single-celled and heterotrophic (using organic carbon as a source of energy), belonging to any of the major lineages of protists and, like most protists, typically microscopic. All protozoans are eukaryotes and therefore possess a “true,” or membrane-bound, nucleus.

2017年4月28日 · Organisms known as protozoa include a wide range of organisms, most of which are free-living single-celled eukaryotes. Therefore, protozoa fit into the Domain Eukarya.

2023年8月3日 · Protozoa may be defined as “microscopic acellular animalcules existing singly or in colonies, without tissue and organs, having one or more nuclei”. Some of the characteristics are: There are about 50,000 known species of Phylum Protozoa.

What is Protozoa? Protozoa are unicellular, eukaryotic, heterotrophic organisms. They are either free-living or parasites. There are around 65000 species of protozoans categorised in different groups. They lack a cell wall.

2024年10月1日 · Protozoa are a diverse group of single-celled eukaryotic organisms that can be either free-living or parasitic. They primarily feed on organic matter, including microorganisms and organic debris. Protozoa are characterized by their lack of a rigid cell wall, motility, and heterotrophic feeding habits.

2025年2月4日 · Protozoa, or protozoans, are single-celled, eukaryotic microorganisms. Some protozoa are oval or spherical, others elongated. Still others have different shapes at different stages of the life cycle. Cells can be as small as 1 μm in diameter and as large as 2,000 μm, or 2 mm (visible without magnification).

2024年10月20日 · Protozoa, as single-celled eukaryotes, possess a complex cellular architecture that supports their functions and adaptability. Central to their structure is the nucleus, housing the organism’s genetic material.

2022年10月14日 · Protozoa are single-celled organisms that can sometimes cause diseases. Common protozoan diseases include malaria, giardia, and toxoplasmosis. Diagnosing protozoan illness may involve blood tests, stool tests, or biopsies, depending on which protozoa a healthcare provider suspects.

Protozoa (in Greek proto = first and zoa = animals) is a diverse group of single-celled, microscopic or near-microscopic eukaryotes (organisms whose cells have nuclei) that commonly show characteristics usually associated with animals, most notably mobility and heterotrophy.

2023年9月21日 · Protozoa is the term applied to a group of single-celled eukaryotes that can range in size from micrometers to several millimeters, representing a genetically diverse branch of early life that emerged in the pre-Cambrian era and shares common ancestors with, though is not, a plant, animal, or fungus.

2024年10月1日 · Protozoa can be broadly categorized into two primary forms of life: free-living, found in various aquatic environments (including freshwater and seawater), and parasitic, which may reside externally (ectoparasites) or internally (endoparasites) within host organisms.

Protozoa are micro-organisms which have a membrane bound nucleus that can't be categorised as a fungi, animal or plant. Most protozoa are free living, but some are parasitic. They are heterotrophs, meaning that they eat other plants or animals for energy and nutrients.

2018年12月19日 · Protozoa, also known as protozoans, are single-celled parasitic or free-living eukaryotes which feed on debris and organic matter. Historically, a protozoan was considered a "one-celled animal" because it had various animal-like behaviors including predation, a lack of cell wall, and motility.

2024年9月20日 · Protozoa are single-celled eukaryotic microorganisms that belong to the kingdom Protista. They exhibit diverse forms and functions, living in various environments, including water and soil. Protozoa can be free-living or parasitic, and they often reproduce asexually through binary fission.

2023年8月31日 · Protozoa are unicellular eukaryotic microorganisms lacking a cell wall and belonging to the Kingdom Protista. Although there are nearly 20,000 species of protozoa, relatively few cause disease; most inhabit soil and water.

Animal-like protists are called protozoa. Most consist a single cell. Like animals, protozoa are heterotrophic and capable of moving. Examples of protozoa include amoebas and paramecia.

Protozoa are a highly diverse group of eukaryotic unicellular organisms having a wide range of size, morphological characteristics and physiological properties. They have been placed in the subkingdom Protozoa under the kingdom Protista by Whittaker in 1969.