Question

Pharyngeal nephridia of Pheretima occur in which of the following segments?

• A. 3, 4 and 5
• B. 4, 5 and 6
• C. 5, 6 and 7
• D. 6, 7 and 8

Answer 1

Answer: (B)

4, 5 and 6

The pharyngeal nephridia occur as paired tufts surrounding the alimentary canal in the 4${}^{th}$, 5${}^{th}$ and 6${}^{th}$ segments. A large number of nephridia are grouped together to form each tuft. The terminal ducts of all the nephridia unite to form a common excretory duct. So, the correct answer is option B.