Simple photoreceptors in Limulus polyphemus.

摘要: The "olfactory nerve," the endoparietal eye, and rudimentary lateral eyes of Limulus (polyphemus) contain simple photoreceptor cells that duplicate many electrical responses retinular eye; are a receptor potential consisting aninitial transient phase subsequent steady phase,low-amplitude fluctuations, small locally regenerative response to pulses both light current. Photic stimulation does not induce conducted action potentials, but increase membrane conductance. potentialrequires presence sodium ions in external medium. Measurements absorption spectra indicate photopigment whose maximum is with wavelength 535 nanometers. functional significance these has been ascertained.