Protozoa (EXAM IV) Flashcards
Protozoa have typically been classified as:
Parasites
What is a parasite?
An organism that lives on or within another organism (the host) and benefits from the association while harming the host
Where does a parasite typically obtain its nutrients from?
Host
Types of parasites include:
Protozoa & Helminths
Protozoa can be described as a:
Diverse group of eukaryotic microbes
How are protozoa related?
Related only by their simple organization
The simple organization relating protozoa includes:
Unicellular or multicellular without specialized tissues
Most protozoa are ____ in ____ environments or on _____
free-living; aquatic; decaying organic matter
Some protozoa are considered _____
Parasitic
Many protozoa are capable of:
Encystation
Formation of a cyst:
Encystation
Formation of a cyst by protozoa involves a ______ state with:
resting state; with a wall & low metabolic activity
Describe the metabolic activity of protozoa during encystation:
Low metabolic activity
List the function of cysts: (3)
- Protection from changes in environment
- Sites for nuclear reorganization & cell division
- Transfer from one host to another
Escape from vegetative form from cyst:
Encystation
Encystation is usually triggered by:
- Return to favorable environment
- Entry into new host
What is the vegetative form released by parasitic species:
Trophozoite
Discuss the locomotion or protozoa:
Some are nonmotile some are motile
The motile species of protozoa use one of the following:
-Cilia
-Flagella
-Psuedopodia
Psuedopodia are:
Cytoplasmic extensions
Reproduction of protozoa may be:
Asexual or sexual
Asexual reproduction of protozoa typically occurs through:
Binary fission
Describe the binary fission:
Mitosis followed by cytokinesis
Sexual reproduction of protozoa typically occurs through:
Conjugation
Describe conjugation:
Exchange of gametic nuclei between paired protozoa of opposite mating types
Zooflagellates are motile due to:
One or more flagella
Species of protozoa that cause Giardiasis:
Giardia Lamblia
Giardiasis is a:
Gastrointestinal disorder
Species of protozoa that cause Trichomoniasis:
Trichomonas Vaginalis
Trichomoniasis is a:
Sexually transmitted disease
Hemoflagellates that are important blood pathogens:
Trypanosomes
Trypanosomes are:
Hemoflagellates (AKA blood parasites)
Give an example of a Trypanosome:
African sleeping sickness
Most common cause of epidemic waterborne diarrheal disease:
Giardiasis
Giardiasis is a _____ disorder
Gastrointestinal disorder
Giardia lamblia forms ____ & _____
Cysts & trophozoites
Giardia lamblia forms cysts & trophozoites. The trophozoites attach to _____ & interfere with ____
intestinal epithelium; nutrient absorption
Discuss the transmission of Giardia lamblia:
Cyst-contaminated water
Discuss the reservoirs of Giardia lamblia:
numerous animal reservoirs & asymptomatic carriers are common
The clinical manifestations of ________ include- severe diarrhea, epigastric pain, cramps, voluminous flatulence & anorexia:
Acute giardiasis
The clinical manifestations of _____ include- intermittent diarrhea with periodic appearance and remission of symptoms:
Chronic gastritis
What antiprotozoal agents are used for the treatment of giardiasis?
Metronidazole
How might one prevent contraction of giardiasis?
Avoiding contaminated water of puriy it by boiling or filtering (cysts are resistant to chlorine treatment)
The cysts formed in Giardia lamblia are resist to:
Chlorine treatment
One of the most common sexually transmitted diseases:
Trichomonas vaginalis
Trichomonas vaginalis is found in ____ % of women
15%
Trichomonas vaginalis lacks a ____ stage but does produce ____
Cyst stage; trophozoites
Discuss the clinical manifestations of Trichomoniasis:
- accumulation of leukocytes at site of infection
- In female, results in yellow purulent vaginal discharge and itching
- In males usual asymptomatic or burning urination
Discuss how we diagnose trichomonas vaginalis:
Observation of parasite in vaginal discharge, semen or urine
What is the treatment of trichomonas vaginalis:
Antiparasite therapy of metrodiazole
Resides in the mouth; usually associated with poor oral hygiene:
Trichomonas tenax
Trichomonas tenar aspiration is associated with:
Pneumonia
Hemoflagellate diseases are caused by:
flagellated protozoa
Two major groups of flagellated protozoa include:
Leishmanias & trypanosomes
Hemoflagellate diseases are transmitted by:
bites of infected arthropods
Hemoflagellate disease infect:
Blood & tissues of humans
Also called African sleeping sickness:
African trypanosomiasis
African trypanosomiasis is transmitted by:
Tsetse flies
The reservoirs of African trypanosomiasis include:
Domestic cattle & wild animals
African trypanosomiasis symptoms are characterized as:
Chronic bloodstream infections with bouts of parasitemia
what happens after months to years with African trypanosomiasis infection?
CNS invasion
The clinical manifestations of African trypanosomiasis include:
Interstitial inflammation and necrosis within lymph node and small blood vessels of brain & heart, leading to lethargy & death within 1 to 3 years
Disease characterized by interstitial inflammation & necrosis within lymph nodes and small blood vessels of brain & heart leading to lethargy & death in about 1 to 3 years:
African trypanosomiasis
Disease characterized by interstitial inflammation & necrosis within lymph nodes and small blood vessels of brain & heart leading to lethargy & death in about 1 to 3 years:
African trypanosomiasis