Question

Select the correct statements with reference to pheretima (excretory system)
A) Nephridia help in excretion and osmoregulation
B) Septal nephridia collects the wastes from coelomic fluid with the help of nephrostomes
C) Integumentary nephridia discharge waste materials to the outer body surface through the nephridiopores
D) Septal nephridia and pharyngeal nephridia discharge wastes into luman of gut.

• A. $A,B,C$
• B. $B,C,D$
• C. $A,C,D$
• D. $A,B,C,D$

Answer 1

The correct option is A $A,B,C$

Excretion in earthworm is performed by long, thin and coiled tubules known as nephridia.

The septal nephridia are located on both sides of the septa--thread-like structures that hold the skin to organs below 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.

Pharyngeal nephridia discharge waste products directly into the buccal cavity and pharynx. Hence, statement D is incorrect.

So, the correct option is 'A, B, C'.