The crayfish has a cavity or ___________ lined with sensory seta or hairs.A grain in the cavity is pulled downward by gravity;the pressure against the bottom hairs of the cavity gives the crayfish a perception of being upright and when it changes orientation,the grain touches side hairs that make it realize it is not upright.Thus the crayfish "knows" which way is up in the dark.
A)ampulla
B)labyrinth
C)saccule
D)statocyst
E)statolith

Question

Quizplus · Accepted Answer

The cavity described in the passage is the statocyst, which contains a statolith (grain). The sensory seta or hairs are present in the walls of the statocyst.

The Crayfish Has a Cavity or ___________ Lined with Sensory