Question 1

Which of the following cestode infections can increase through autoreinfection?&#10;A) Diphyllobothrium latum&#10;B) Echinococcus granulosa&#10;C) Hymenolepis nana&#10;D) Taenia solium

Accepted Answer

Hymenolepis nana eggs are infective when released, so they may hatch in the GI tract.

Question 2

Consumption of raw or undercooked beef is associated with:&#10;A) Taenia saginata&#10;B) Taenia solium&#10;C) Trichinella spiralis&#10;D) Dipylidium carninum

Accepted Answer

T. saginata, the beef tapeworm, is acquired by ingesting undercooked beef. T. solium is acquired by eating undercooked pork.

Question 3

The cestode that produces an operculated egg is:&#10;A) Diphyllobothrium latum&#10;B) Echinococcus granulosa&#10;C) Hymenolepis nana&#10;D) Taenia solium

Accepted Answer

D. latum produces an operculated egg.

Question 4

For which of the following can humans serve as both the definitive and intermediate host?&#10;A) Diphyllobothrium latum&#10;B) Echinococcus granulosa&#10;C) Taenia saginata&#10;D) Taenia solium

Accepted Answer

T. solium eggs will hatch in humans with larva migrating from the intestine to other body sites, causing the condition known as cysticercosis. Encysted larvae in undercooked pork lead to tapeworm disease if ingested by humans.

Question 5

Which of the following tapeworm infections is associated with vitamin B₁₂ deficiency macrocytic anemia? A) Diphyllobothrium latum B) Hymenolepis nana C) Taenia saginata D) Taenia solium

Accepted Answer

D. latum worms compete with the host for vitamin B₁₂, which can lead to macrocytic anemia in some individuals, especially Scandinavians.

Question 6

Several tapeworm segments recovered in a routine fecal concentration procedure were found to have 7 to 12 lateral uterine branches. This parasite is:&#10;A) Taenia solium&#10;B) Taenia saginata&#10;C) Diphyllobothrium latum&#10;D) Dipylidium caninum

Accepted Answer

Taenia spp. eggs are identical, so typical segments or scolex (following treatment) is needed to properly identify this species.

Question 7

Humans can become an accidental zoophytic host for which of the following if an infected flea is ingested?&#10;A) Dipylidium caninum&#10;B) Echinococcus granulosus&#10;C) Spirometra spp.&#10;D) Taenia solium

Accepted Answer

Only D. caninum has a flea as an intermediate host in its life cycle.

Question 8

The first intermediate host in the Diphyllobothrium latum life cycle is a:&#10;A) Copepod&#10;B) Fish&#10;C) Flea&#10;D) Pig

Accepted Answer

A copepod ingests a free-living coracidium larva, which is, in turn, ingested by a fish that becomes the second intermediate host. Humans ingest encysted larval forms in uncooked fish.

Question 9

Identify the parasite shown in the following view:  &#10;A) Diphyllobothrium latum&#10;B) Echinococcus granulosa&#10;C) Hymenolepis nana&#10;D) Taenia saginata

Accepted Answer

This view is a Diphyllobothrium latum egg. It is the only operculated cestode egg.

Question 10

The structural component in tapeworms that contains the reproductive organs is called the:&#10;A) Onchosphere&#10;B) Proglottid&#10;C) Scolex&#10;D) Strobila

Accepted Answer

The proglottid, also called the segment, is the structure that contains both the male and female reproductive organs. The strobila is the entire body of the tapeworm, which may contain many proglottids.

Question 11

Identify the parasite shown in the following view:  &#10;A) Ascaris lumbricoides&#10;B) Taenia saginata&#10;C) Taenia solium&#10;D) Either b or c&#10;E) None of these

Accepted Answer

The answer of Identify the parasite shown in the following...

Deck 2: Cestoda