Part of these structures present in all vertebrates is derived from the neuromasts that make up the lateral lines. In amniotes, that part of these structures is the only thing to develop from the dorsolateral placode. Parts of these structures develop from the first and second pharyngeal pouches. The Rinne and Weber tests can determine whether certain defects in these structures are (*) conductive or neurological. In these structures, endolymph and perilymph are contained in the membranous and bony labyrinths. (10[1])Those parts of these structures (10[1])contain the semicircular canals, (10[2]-5[1])which are essential for maintaining balance. In these organs, the eighth cranial nerve is connected to hair cells that respond to different frequencies of vibrations. For 10 points, name this organ containing the cochlea that is used for hearing. ■END■ (10[1])