Year: 2015
Genre: Discussion
URL: http://bobnational.net/record/340248
Review by Emma Sterling
“Circadian rhythms are a biological version of a clock inside humans and all other animals, plants and quite possibly in almost every living cell…These rhythms are a response to the most predictable condition of life on earth, that is, dark at night and bright during the day.”
“Circadian rhythms are one of the best examples of how genes relate to behaviour.”
In this episode of his series In Our Time (41 minutes), Melvyn Bragg talks with Professors Russell Foster, Debra Skene and Steve Jones about circadian rhythms, what they are and how they affect behaviour in humans and other organisms.
The programme includes a brief explanation about the subcellular process involved in circadian rhythms. In humans this takes place in what is described as the ‘master pacemaker’, formally known as the suprachiasmatic nuclei (SCN). This is a group of 50,000 cells located in the hypothalamus that are essential for producing the rhythm. Approximately 12-14 genes and their protein products are involved in the molecular feedback loop with an oscillation of approximately 24 hrs. In some individuals these oscillations are slightly longer, in others slightly less. These differences can affect whether that person is a morning or evening person. Other factors that can affect these oscillations include polymorphisms in the genes that control this process, and external factors such as food, drink and caffeine but none of the aforementioned are as important as light. Continue reading