Fig. 6.

Cellular alkaline phosphatase (ALP) activity. There is a significant decrease following the blue light irradiance of cells in comparison with other experimental conditions (*P < 0.001). Mean values with standard deviation (vertical bars) are presented. Filtered 40 Hz‐pulsed light predominant irradiance: red—593–840 nm, green—56–650 nm, blue—420–580 nm, control—cells kept in dark, positive control—cells kept in dark and treated with activin 100 ng mL⁻¹.