http://webvision.med.utah.edu/anatomy.html

Does the Human Body Transmit and Receive EM Signals?

Yes. A simple example of this is with the retina of the eye. Reflected light from the sun is the transmitter and the photoreceptor molecules are the receivers. Light is transmitted to the eye and molecules called “photoreceptors” receive these EM signals and convert these to electricity. This phenomena is similar to listening to one’s local radio where the FM station is functioning as an EM transmitter and one’s home radio is functioning as the EM receiver.