25 Questions
The learning outcome of this course is to understand the features and ______ of protozoa.
life cycle
The objective of this course is to classify protozoa into different ______.
phyla
The subphylum Sarcodina includes the genus ______.
Amoeba
The protozoan Entamoeba histolytica is found in the ______.
colon
The protozoan Giardia lamblia is found in the ______ intestine.
small
Giardia lamblia has a ______ shape.
pear
Giardia lamblia has ______ flagella.
8
The transmission of Giardia lamblia occurs through the ______ route.
fecal-oral
Giardia lamblia belongs to the phylum ______.
Sarcomastigophora
Giardia lamblia has ______ nucleus.
2
The diameter of the Giardia lamblia is about ______ mm.
8-12
The nucleus of Giardia lamblia is ______ and has a small eccentric karyosome.
four
The Giardia lamblia cyst has a clear space beneath the ______ cyst wall.
thin
Infection of Giardia lamblia occurs by the ingestion of ______ in contaminated water, food, or by the fecal-oral route.
cysts
The process of ______ releases trophozoites in the small intestine.
excystation
Giardia lamblia can be detected in a ______ specimen
stool
Trichomonas vaginalis is transmitted through ______ contact
sexual
Kohn staining is used for the detection of ______ cysts
Giardia
Trichomonas vaginalis has ______ anterior flagella
4
Giardia lamblia has a ______ motility
graceful falling-leaf
The parasitic form called ______ is sensitive to environmental changes and it disintegrates rapidly upon release from the body.
trophozoite
The morphological forms of Naegleria fowleri can be _______, ______ and ______.
amoeboflagellate, amoebic, flagellate
Peripheral nuclear chromatin is absent in ______ and ______.
E.histolytica, E.coli
Free living amoeba include ______ and ______.
Naegleria, Acanthamoeba
Diseases caused by Acanthamoeba spp. are ______ and ______.
meningoencephalitis, keratitis
Study Notes
Protozoa of Medical Importance
- Protozoa are divided into four phyla: Sarcomastigophora, Ciliophora, Apicomplexa, and Microspora.
Subphylum Sarcodina (= Amoeba)
- Found in colon, liver, and lungs.
- Examples include:
- Entamoeba histolytica
- Entamoeba coli
- Endolimax nana
- Iodamoeba butschlii
- Blastocystis hominis
Subphylum Mastigophora (= Flagellates)
- Found in small intestine.
- Examples include:
- Giardia lamblia
- Trichomonas vaginalis
- Dientamoeba fragilis
Giardia lamblia
- Found in lakes, streams, and other water sources worldwide.
- Transmission occurs through the fecal-oral route, primarily through contaminated food and water.
- Characteristics:
- Pear-shaped with 8 flagella.
- Length: 9-21 mm, width: 5-15 mm.
- Bilaterally symmetrical with 2 nuclei, one on either side of the axostyle.
- Fine granular cytoplasm with 2 median parabasal bodies.
- Life cycle:
- Excystation occurs in the small intestine, releasing trophozoites.
- Trophozoites multiply by longitudinal binary fission, remaining in the lumen of the proximal small bowel.
- Encystation occurs as the parasites transit towards the colon.
- Cysts are the infectious stage, found commonly in non-diarrheal feces.
Diagnostic Techniques for Giardia lamblia
- Examination of triple fecal tests from non-consecutive days.
- Concentration technique and permanent stain smear.
- Stool specimen examination using Kohn staining and trichrome staining.
Trichomonas vaginalis
- Found in the vagina and urethra.
- Distribution: worldwide, with higher prevalence among persons with multiple sexual partners.
- Transmission occurs through:
- Sexual contact.
- Contaminated towels and examination equipment.
- Infants may be infected during birth.
- Characteristics:
- Pear-shaped with 3-5 anterior flagella and an undulating membrane.
- Length: 10-30 mm, width: 5-20 mm.
- Ovoid nucleus at the anterior end.
- Axostyle from anterior to posterior, ending like a tail.
- In males, it infects the urethra, seminal vesicle, and prostate, causing urethritis.
- In females, it infects the vulva, vagina, and cervix, causing vaginitis.
- Treatment: metronidazole or quinacrine.
Test your knowledge of E. Histolytica and E. Coli characteristics, including their life cycles, nucleus, and infection symptoms.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
