Fotoperioodi

Fotoperioodi refers to the duration of light and darkness within a 24-hour period. This daily cycle is a crucial environmental cue for many organisms, influencing a wide range of physiological and behavioral processes. Plants, for example, use photoperiod to regulate flowering, seed germination, and the timing of dormancy. Short-day plants flower when the nights are long (days are short), while long-day plants flower when the days are long (nights are short). Day-neutral plants are not significantly affected by photoperiod. Animals also respond to changes in photoperiod. Seasonal breeders often time their reproductive cycles according to the lengthening or shortening of days, as this can signal favorable environmental conditions for raising young. Migration patterns, hibernation, and molting in animals can also be influenced by photoperiodic signals. The underlying mechanism often involves photoreceptor proteins like phytochromes in plants and cryptochromes in both plants and animals, which detect light and trigger internal responses. These responses ultimately help organisms synchronize their life cycles with the changing seasons and environmental conditions, ensuring survival and reproductive success.