Final answer:
The development of a cercaria from a miracidium in Schistosoma occurs in a freshwater snail. This process is part of the lifecycle of the parasitic flatworm that causes schistosomiasis, a disease prevalent in tropical regions.
Step-by-step explanation:
When Schistosoma eggs are excreted in the urine or feces of an infected human, they hatch into miracidia upon contact with fresh water. These miracidia then infect freshwater snails. Inside the snail hosts, miracidia undergo several developmental stages and eventually transform into cercariae, which are released back into the water. These cercariae are equipped to infect a new human host by penetrating the skin, completing the parasite's life cycle. This cycle is a significant health concern, as it leads to schistosomiasis, a disease that can cause organ damage and is prevalent in tropical regions.
After the eggs of Schistosoma are released into the water by an infected human host, they hatch into miracidia. These miracidia infect a specific species of snail, which serves as the intermediate host. Inside the snail, the miracidia develop into cercariae. The cercariae, which are the next stage of development, leave the snail and enter the water. They can then penetrate the skin of swimmers and bathers, eventually entering the bloodstream and maturing into adult worms.