Question

Which is an incorrect statement of pheretima excretory organs?

(1) Septal nephridia are present only one side of the septum from 15 to last
(2) Nephridia regulate the volume and composition of body fluids.
(3) A nephridium starts out like a funnel that collects excess fluid from the Coelomic chamber.
(4) Pharyngeal nephridia discharge the waste material into the buccal cavity and pharynx.

Answer 1

• Statement 'Septal nephridia are present only one side of the septum from 15 to last' is incorrect.
• The septal nephridia are located on both sides of the septa--thread-like structures that hold the skin to organs below it--in rows of forty or fifty individual nephridia. They appear after the 15th segment, and they empty into a pair of excretory ducts that lead to the main gut cavity.