Biology 1001A Lecture Notes - Cyanobacteria, Wild Type, Bioluminescence

• School: Western University
• Department: Biology
• Course: Biology 1001A
• Professor: Tom Haffie

Document Summary

Biological rhythm with a period of around a day (24 hours) The biological clock can be set by the external environment (astronomical time); called entrainment. It is not totally independent of external environment. You can set the clock, but you are not a slave to the external environment; called free- running clock. If environment becomes constant, clock still works. Eventually, free running clock may become whacked but then you can entrain it again. Ways to distinguish circadian from non-circadian diurnal rhythms - Non-circadian diurnal rhythms respond to the external environment completely. Photosynthesis as a process is non-circadian as it depends completely on the external environment (light) Mechanism of oscillating gene expression in neurospora biological clock (frq expression) - The oscillation of the biological clock is the oscillation of transcription and translation of clock genes such as frq. Wc-1 and wc-2 are transcription factors for frq gene, bind to promoter and stimulate transcription.