What is the peak photoreceptor absorption spectra of a L cone?

The peak photoreceptor absorption spectrum of a L cone, which is responsible for detecting long wavelengths of light, is at approximately 557 nm. This wavelength corresponds to the absorption of light that these cones are most sensitive to, primarily in the red region of the visible spectrum.

Understanding the function of the L cone is essential in visual perception as it plays a crucial role in color discrimination, particularly in distinguishing reds and greens. In normal color vision, the L cones work in tandem with M (medium-wavelength) and S (short-wavelength) cones to create a full palette of colors. The specific peak absorption characteristic of the L cones at 557 nm is a fundamental aspect of human photopic vision, particularly under well-lit conditions.

The other choices represent wavelengths associated with other types of cones or different spectral sensitivities. The 426 nm relates to the S cones, which are most sensitive to shorter wavelengths in the blue region, while 507 nm corresponds to the peak sensitivity of the M cones, which respond to medium wavelengths. The 530 nm choice does not accurately reflect the peak response of any of the primary cone types and thus is not relevant to L cone physiology.