Photochemical reactions in biological light perception and regulation

In English Many photochemical reactions involved in the sensing of and regulation by light and ultraviolet radiation by organisms consist of cis-trans (and trans-cis) isomerisations. This chapter starts with a description of these, and then goes on to the blue-light receptors crypto-chrome and phototropin, which use other chemical mechanisms, and concludes with a discus-sion of ultraviolet-B receptors.