What are semicircular canals in cyclostomes?

(1) a part of membranous labyrynth

(2) part of gills

(3) both (1) and (2)

(4) none of these

Themembranous labyrinthis a collection of fluid filled tubes called as semicircular canals and chambers which contain the receptors for the senses of equilibrium and hearing.
So ans is 1)

for more info:
Semicircular canal are a part of membarnous labyrinth.Petromyzon have only two and hagfishes just one semicircular canal.Cyclostomes have degenerated membranous labyrinth due to their parasitic mode of life. As they have no paired fins, lampreys and hagfishes do not seem to have three dimensional sense of things.

Approved