Question

Match the following list of animals with their level of organization and choose the correct sequence:

	Column - I		Column - II
(A)	Organ level	(P)	Pheretima
(B)	Cellular aggregate level	(Q)	Fasciola
(C)	Tissue level	(R)	Spongilla
(D)	Organ system level	(S)	Obelia

• A. A- (S), B- (R), C- (P), D- (Q)
• B. A- (S), B- (Q), C- (R), D- (P)
• C. A- (Q), B- (S), C- (R), D- (P)
• D. A- (Q), B- (R), C- (S), D- (P)

Answer 1

The correct option is D A- (Q), B- (R), C- (S), D- (P)

Fasciola is a parasitic trematode of the class Trematoda, belonging to phylum Platyhelminthes which has organ level organisation.

The cellular aggregate level organisation can be seen in Spongilla which belongs to phylum Porifera.

Tissue level organisation can be seen in Obelia as they have simple tissues which perform the metabolic function.

Organ system-level organisation can be seen in Pheretima where the specialised organ is developed for metabolic activity.

So, the correct answer is option D.