MICRO Ch 23 review

Which of the following arthropod vectors may spend its entire lifetime in association with a single individual?

lice

After an initial infection with Naegleria, what body system will be invaded by the parasite next?

central nervous system

Amoebae are a group of protozoa that move and feed using __________.

lobe-shaped pseudopods

The salivary glands of a tsetse fly will contain which of the following forms of Trypanosoma brucei?

mature infective forms

Which are the most important vectors of parasitic diseases in humans?

mosquitos

Which of the following is the most important arthropod vector of human diseases?

mosquitos

What type of disease does Trypanosoma cruzi cause?

heart disease

The number of cases of schistosomiasis has decreased over the past few decades due to which of the following?

improvement in water systems

The _____ form of the parasite has a characteristic "ring" shape.

trophozoite

There are four species of Plasmodium that cause the disease malaria, of which P. falciparum is the most virulent. P. falciparum is transmitted by a mosquito vector to a human host. Can all mosquitoes transmit malaria? Why or why not?

Only female Anopheles mosquitoes can transmit the malarial parasite to a human host because they are the only ones who take a blood meal from the host.

Giardiasis is one of the more common GI diseases in the United States. Both animals and humans are at risk for developing this disease. In which of these cases would a human be most likely to become infected by this pathogen?

A family hiking in the woods allows its dog to drink from a nearby stream. When they return home, the dog becomes sick with diarrhea in the house and family members must clean up the mess

A patient infected with a protozoan parasite who also exhibits congestive heart failure is most likely in the final stages of which of the following diseases?

Chagas' disease

Which of the following organisms can cause water-borne diarrheal disease?

Cryptosporidium enteritis Vibrio cholerae Entamoeba histolytica

What is dysentery?

Diarrhea with blood and mucus

Which stage of Plasmodium is formed within vesicles inside the liver and is released into the bloodstream?

Merozoites

What is the most common way to diagnose ascariasis?

Microscopic identification of the eggs in the stool

Which species of Plasmodium typically causes the most serious disease?

P. falciparum

Which of the following phases of infection occurs in the mosquito?

Sporogony phase

Malaria used to be endemic in the U.S., but has not been prevalent for decades. How is this possible?

The U.S. initiated a mosquito eradication program.

A child with a pinworm infection is successfully treated, but later suffers a relapse. Which of the following best explains the relapse?

The child's clothing and bedding were not properly laundered

Which vector is required for the spread of malaria?

The female Anopheles mosquito.

Are tsetse flies and kissing bugs biological or mechanical vectors of Trypanosoma brucei and T. cruzi, respectively?

They are both biological vectors

What is the role that snails play in the transmission of flukes?

They are intermediate hosts.

Which form of leishmaniasis is most likely to be fatal?

Visceral leishmaniasis

What is cysticercosis?

When larvae from a pork tapeworm encyst in a person's muscles

What is the most common symptom of pinworm infestation?

anal itching

Which of the following groups of protozoan parasites is typically nonmotile?

apicomplexans

Diagnosis of malaria relies on identification of trophozoites in a __________.

blood spear

Which is the infective stage of an intestinal protozoan?

cyst

Which of the following is correctly matched?

definitive host: mature forms reproduce

The release of large quantities of merozoites into circulation at one time is due to a form of reproduction by Plasmodium known as __________.

schizogony

Which of the following poses the greatest risk of contracting schistosomiasis?

swimming in contaminated water

Which of the following phases of malaria occurs in humans?

the erythrocytic cycle

What method is the LEAST effective for controlling malaria?

vaccination against P. falciparum

Which type of leishmaniasis is most likely fatal?

visceral leishmaniasis