THE VISUAL PIGMENTS 



during the initial photochemical change from rhodopsin to transient 

 orange (cf. Chap. 4, p. 124). 



AND IN BLEACHED SOLUTIONS OF OTHER VISUAL PIGMENTS 



The regeneration phenomena just described and the conclusions 

 drawn therefrom apply to cattle rhodopsin, though there is a strong 



500 

 Wavelength in m/x 



Fig. 5.8. Dependence of the negative portion of the carp (pigment 523) 

 difference spectrum on the wavelength of the bleaching light. (A) O, 

 changes caused by 21 hr exposure to violet light (430 m^); +, total 

 changes caused by this and by an additional 1 8 hr exposure to red hght 

 (630 mju). (B) +, changes caused by 19 hr exposure to the red light; 

 O, total changes caused by this and by an additional 18 hr exposure to 

 the violet light; data displaced 30 ordinate units from (a). (C) +, 

 changes caused by 2 hr exposure to green light (530 m^); O, total 

 changes caused by this and by an additional 18 hr exposure to the 

 violet light. Data displaced 60 ordinate units from (a). pH 8-2, 



T = 20°C. 

 {Crescitelli and Dartnall, 1954) 



148 



