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Updated: Jun 19, 2026

Determination of Photoreceptor Cell Spectral Sensitivity in an Insect Model from In Vivo Intracellular Recordings
Published on: February 26, 2016
THE PHOTOCHEMICAL NATURE OF THE PHOTOSENSORY PROCESS
1Physiological Laboratory, College of Medicine, Creighton University, Omaha.
Abstract:
1. In order to produce a response in Mya, the minimum amount of light energy required is 5.62 meter candle seconds. This energy follows the Bunsen-Roscoe law for the relation between intensity and time of exposure. 2. The necessary minimum amount of energy varies but little with the temperature; the temperature coefficient for 10 degrees C. is 1.06. 3. In view of these facts it is concluded that the initial action of the light is photochemical in nature. This substantiates the hypothesis previously suggested to account for the mechanism of photoreception. 4. The constant energy requirement for stimulation of Mya shows that the traditional division of animals into those which respond to a constant source of light and those which respond to a rapidly augmented light is without any fundamental significance for sensory physiology.
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