In Brief:
Among the landmarks of human achievement, a major milestone was reported in 2000-the completion of a rough draft of the sequence of the human nuclear genome. Work in the late 1990s led to the view that plaque formation may be a response to chronic inflammation of the innermost arterial layer. Circadian rhythms are patterns of biological activity and rest attuned to the 24-hour day, and they are seen in virtually all animals and plants. What serves to reset many biological clocks is light-specifically, blue light. In mutant organisms with specific defects in cryptochrome, blue light fails to reset the circadian rhythms, which drift with respect to the 24-hour day. In the case of cryptochrome, the energy of blue light is somehow used to signal the nervous system to reset the biological clock.
