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
Podcast Episodes
Superconductivity [not-audio_url] [/not-audio_url]

Duration: 50:44
Melvyn Bragg and guests discuss the discovery made in 1911 by the Dutch physicist Heike Kamerlingh Onnes (1853-1926). He came to call it Superconductivity and it is a set of physical properties that nobody predicted and…
The Challenger Expedition 1872-1876 [not-audio_url] [/not-audio_url]

Duration: 51:14
Melvyn Bragg and guests discuss the voyage of HMS Challenger which set out from Portsmouth in 1872 with a mission a to explore the ocean depths around the world and search for new life. The scale of the enterprise was br…
The Fish-Tetrapod Transition [not-audio_url] [/not-audio_url]

Duration: 55:33
Melvyn Bragg and guests discuss one of the greatest changes in the history of life on Earth. Around 400 million years ago some of our ancestors, the fish, started to become a little more like humans. At the swampy margin…
The Electron [not-audio_url] [/not-audio_url]

Duration: 49:47
Melvyn Bragg and guests discuss an atomic particle that's become inseparable from modernity. JJ Thomson discovered the electron 125 years ago, so revealing that atoms, supposedly the smallest things, were made of even sm…
The Death of Stars [not-audio_url] [/not-audio_url]

Duration: 58:09
Melvyn Bragg and guests discuss the abrupt transformation of stars after shining brightly for millions or billions of years, once they lack the fuel to counter the force of gravity. Those like our own star, the Sun, beco…
Homo erectus [not-audio_url] [/not-audio_url]

Duration: 51:03
Melvyn Bragg and guests discuss one of our ancestors, Homo erectus, who thrived on Earth for around two million years whereas we, Homo sapiens, emerged only in the last three hundred thousand years. Homo erectus, or Upri…
Seismology [not-audio_url] [/not-audio_url]

Duration: 49:35
Melvyn Bragg and guests discuss the study of earthquakes. A massive earthquake in 1755 devastated Lisbon, and this disaster helped inspire a new science of seismology which intensified after San Francisco in 1906 and adv…
William and Caroline Herschel [not-audio_url] [/not-audio_url]

Duration: 50:56
Melvyn Bragg and guests discuss William Herschel (1738 – 1822) and his sister Caroline Herschel (1750 – 1848) who were born in Hanover and made their reputation in Britain. William was one of the most eminent astronomers…
Corals [not-audio_url] [/not-audio_url]

Duration: 51:35
Melvyn Bragg and guests discuss the simple animals which informed Charles Darwin's first book, The Structure and Distribution of Coral Reefs, published in 1842. From corals, Darwin concluded that the Earth changed very s…
The Manhattan Project [not-audio_url] [/not-audio_url]

Duration: 48:20
Melvyn Bragg and guests discuss the race to build an atom bomb in the USA during World War Two. Before the war, scientists in Germany had discovered the potential of nuclear fission and scientists in Britain soon argued…