Light response refers to the way living organisms react to light stimuli. This can include processes like photosynthesis in plants, where they convert light energy into chemical energy, or the way animals adjust their behavior based on the presence of light, such as birds migrating with the changing seasons. In humans, light response is crucial for regulating circadian rhythms, which are the body's internal clocks that dictate sleep-wake cycles. The retina in the eye detects light and sends signals to the suprachiasmatic nucleus in the brain, helping to synchronize various bodily functions with the day-night cycle.