Free Radicals

Free Radicals

Author: BBC Radio 4 November 1, 2018 Duration: 51:03

Melvyn Bragg and guests discuss the properties of atoms or molecules with a single unpaired electron, which tend to be more reactive, keen to seize an electron to make it a pair. In the atmosphere, they are linked to reactions such as rusting. Free radicals came to prominence in the 1950s with the discovery that radiation poisoning operates through free radicals, as it splits water molecules and produces a very reactive hydroxyl radical which damages DNA and other molecules in the cell. There is also an argument that free radicals are a byproduct of normal respiration and over time they cause an accumulation of damage that is effectively the process of ageing. For all their negative associations, free radicals play an important role in signalling and are also linked with driving cell division, both cancer and normal cell division, even if they tend to become damaging when there are too many of them.

With

Nick Lane Professor of Evolutionary Biochemistry at University College London

Anna Croft Associate Professor at the Department of Chemical and Environmental Engineering at the University of Nottingham

And

Mike Murphy Professor of Mitochondrial Redox Biology at Cambridge University

Producer: Simon Tillotson


Melvyn Bragg and a panel of academic experts gather each week to explore the vast history of scientific thought on In Our Time: Science. This BBC Radio 4 podcast delves far beyond simple explanations, instead tracing the long and often winding paths of discovery that shaped our understanding of the world. Each episode focuses on a single idea, from the concept of zero to the theory of plate tectonics, unpacking its origins, the controversies it sparked, and the key figures who championed or challenged it. You’ll hear lively, in-depth conversations that place science firmly within its human and historical context, revealing how principles we take for granted today were hard-won through centuries of debate, accident, and insight. The discussions are rigorous and accessible, designed for the curious mind eager to appreciate not just what we know, but how we came to know it. By treating science as a deeply historical endeavour, this series offers a richer appreciation of the discipline itself. Tune in for a thoughtful and engaging journey through the experiments, the arguments, and the brilliant flashes of imagination that have defined our quest for knowledge.
Author: Language: English Episodes: 100

In Our Time: Science
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