Chapter 36 - Regulation of Plant Growth - 36.4 - Photoreceptors Initiate Developmental Responses to Light - 36.4 Recap - Learning Outcomes - Page 783: 2

Red light is used to control germination. For example, lettuce seeds require just a flash of dim light to germinate. Interestingly, the responses generated by red light can be reversed by far red light, approximately at 710 to 740 nanometers. If lettuce seeds were exposed to alternating red light and far red light flashes, they would only demonstrate the response that is stimulated by the last flash.

Red light is used to control germination. For example, lettuce seeds require just a flash of dim light to germinate. Interestingly, the responses generated by red light can be reversed by far red light, approximately at 710 to 740 nanometers. If lettuce seeds were exposed to alternating red light and far red light flashes, they would only demonstrate the response that is stimulated by the last flash.