Light absorbing pigments

Figure 12.4 The light-absorbing pigment retinal undergoes a conformational change called isomerization, when it absorbs light.

Bacteriochlorophyll- Light-absorbing pigment found in green sulfur and purple sulfur bacteria. 

Light-absorbing pigments differentiate rod cells for black-white vision and three types of cone cells for color vision 807... 

It is observable, even with single cells and for virtually all organisms.1061-10623 In most instances the cycle becomes synchronized with the daily light-dark cycle with the aid of suitable light-absorbing pigments often crytochromes (see Chapter 23, Section 1,1). However, the cycle can be observed in various ways under conditions of constant light intensity and temperature. 

If the rate of photosynthesis versus the incident wavelength of light is plotted, an action spectrum is obtained. How can the action spectrum provide information about the nature of the light-absorbing pigments involved in photosynthesis ... 

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