Protozoa

These flashcards cover key terms and definitions related to protozoa and their classifications, diseases, and methods of infection.

Protozoa

Single-celled organisms that can have complex life cycles and are categorized based on mobility, reproduction, and habitat.

Entamoeba histolytica

A pathogenic amoeba causing amebiasis, characterized by the ability to invade intestinal mucosa and potentially leading to dysentery.

Naegleria fowleri

A free-living amoeba that causes Primary Amebic Meningoencephalitis (PAM) when introduced through the nasal cavity.

Acanthamoeba spp.

Free-living amoebas that can cause Granulomatous Amebic Encephalitis (GAE) and keratitis, primarily affecting immunocompromised individuals.

Dientamoeba fragilis

An intestinal flagellate that does not form cysts and may cause gastrointestinal symptoms. It has a unique diagnostic characteristic of two nuclei.

Giardia lamblia

A flagellated protozoan that causes giardiasis, often leading to diarrhea and malabsorption, transmitted via contaminated water or food.

Trichomonas vaginalis

A sexually transmitted protozoan that causes trichomoniasis; characterized by motility and the absence of a cyst stage.

Balantidium coli

The only ciliate pathogenic to humans, causing balantidiasis, which may involve invasion of the intestinal submucosa.

Plasmodium species

A genus of protozoans that includes species responsible for malaria, transmitted by Anopheles mosquitoes.

Chagas disease

A disease caused by Trypanosoma cruzi, transmitted by the bite of the reduviid bug, often leading to serious cardiovascular and gastrointestinal complications.

Excystation

The process of cysts breaking open to release trophozoites in the intestines.

Binary fission

A method of asexual reproduction commonly used by protozoa to multiply.

Flagella

Whip-like structures that enable mobility in certain protozoa.

Pseudopodia

Temporary projections of the cell membrane in amoebae used for movement and feeding.

Cysts

Dormant and resistant forms of protozoa that can survive harsh conditions and facilitate transmission.

Trophozoites

The active, motile form of a protozoan that is typically involved in feeding and reproduction.

Olfactory lobes

Parts of the brain that Naegleria fowleri travels through to reach the central nervous system.

Amoebic dysentery

Severe diarrhea caused by Entamoeba histolytica, often with blood or mucus in the stool.

Infective stage

The stage of a parasite when it can cause infection in a host.

Antigen-based immunoassays

Tests used for diagnosing infections by detecting specific antigens in patient samples.