The life-cycle stages of the intestinal trematodes after the eggs are shed from the body via feces are best described as:

a. cercariae, miracidium larva, metacercariae, and redia.
b. redia, metacercariae, cercariae, and mira-cidium larva.
c. miracidium larva, redia, cercariae, and metacercariae.
d. metacercariae, miracidium larva, cercariae, and redia.


C
The adult worms are located in the small intestine, where they lay eggs, which may be embryo-nated or remain unembryonated until they are shed from the body via feces. The egg continues developing after reaching the water, and a ciliated, free-swimming miracidium larva is released. The miracidium enters a snail host and develops into a redia, followed by development into a tailed cercaria. The cercariae emerge from the snail and encyst as a metacercariae on water plants or fish.

Biology & Microbiology

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