Untitled Deck Flashcards
(35 cards)
What are protozoa?
Protozoa are single-celled eukaryotic organisms that share characteristics with animals, such as mobility and heterotrophy.
What does heterotrophy mean?
Heterotrophy means that protozoa derive their nutrition from complex organic substances.
How are protozoa classified?
Protozoa are classified under the subkingdom Protista, alongside algae and slime molds.
What are the four main groups of protozoa based on movement?
The four main groups are Amoebas, Flagellates, Ciliates, and Sporozoa (Apicomplexans).
How do amoebas move?
Amoebas move using pseudopodia.
How do flagellates move?
Flagellates move using flagella.
Example: Giardia lamblia.
How do ciliates move?
Ciliates move using cilia.
Example: Balantidium coli.
How do sporozoa (apicomplexans) move?
Sporozoa form capsules and spores.
Example: Plasmodium.
What are some intestinal flagellates?
Intestinal flagellates include Giardia lamblia, Chilomastix mesnili, Retortamonas intestinalis, and Trichomonas hominis.
Where is Trichomonas vaginalis found?
Trichomonas vaginalis is found in the urogenital tract.
What is the fecal-oral transmission route?
Fecal-oral transmission occurs when cysts or trophozoites passed in feces contaminate food or water sources.
What are risk factors for transmission of intestinal protozoa?
Risk factors include poor personal hygiene, inadequate hygiene facilities, mass food preparations, food handlers, water treatment failures, and poor sanitation.
What is the general life cycle of intestinal protozoa?
The life cycle involves cysts and trophozoites being passed in feces, excystation in the small intestine, migration to the large intestine, and encystment under unfavorable conditions.
What is Entamoeba histolytica?
E. histolytica is the only pathogenic amoeba that infects humans.
How does infection with E. histolytica occur?
Infection occurs through ingestion of cysts in contaminated water or vegetables.
What are the clinical manifestations of E. histolytica infection?
Clinical manifestations range from asymptomatic infection to invasive intestinal amebiasis and invasive extraintestinal amebiasis.
What is the pathology of E. histolytica?
Trophozoites invade the colon mucosa, causing ulceration and forming flask-shaped ulcers.
What are the symptoms of intestinal amoebiasis?
Symptoms include abdominal pain, loose stools, blood-streaked mucus in diarrhea, and tenderness around the anal region.
How is E. histolytica diagnosed?
Diagnosis involves identifying vegetative forms with red blood cells in the cytoplasm or cysts with 2-4 nuclei in loose stool.
What is Naegleria fowleri?
Naegleria fowleri is a free-living, bacteria-eating amoeba commonly known as the ‘brain-eating amoeba’.
Where is Naegleria fowleri found?
Naegleria fowleri is found in warm freshwater sources and soil near warm-water discharges.
How does Naegleria fowleri transmit?
Transmission occurs through inhalation of the flagellate form while swimming or diving in contaminated water.
What are the symptoms of Naegleria fowleri infection?
Symptoms include fever, nausea, headache, stiff neck, and ultimately death.
What is the treatment for Naegleria fowleri infection?
Treatment for Naegleria fowleri infection is not effective.
