Summary
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
Transcript
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| 0:00.0 | BBC Sounds Music Radio Podcasts |
| 0:04.8 | Thanks for downloading this episode of In Our Time. |
| 0:07.5 | There's a reading list to go with it on our website and you can get news about our programs |
| 0:11.4 | if you follow us on Twitter at BBC In Our Time. |
| 0:14.8 | I hope you enjoyed the programs. |
| 0:16.6 | Hello, we'll be talking about free radicals. |
| 0:18.8 | Free radicals are highly reactive atoms or molecules and we can't live without them or |
| 0:23.0 | sometimes live with them. |
| 0:25.0 | If all their electrons were paired up, they'd be stable. |
| 0:28.3 | But some of one electron, which is unpaired and are always looking to strip an electron |
| 0:32.0 | from a nearby molecule to make up the pair and that neighbor then takes one from another |
| 0:36.5 | and so it goes on and on. |
| 0:38.2 | It's a chain reaction that's great for sending signals, right, our bodies, or making long |
| 0:42.1 | molecules such as for polythene, but it's also highly destructive if unchecked. |
| 0:46.9 | And it's when the free radicals have free reign that they're linked to disease and cell |
| 0:50.8 | damage. |
| 0:51.8 | Sometimes they've been blamed for the entire aging process so that's contested. |
| 0:56.4 | Did me to discuss free radicals on nickelane, Professor Aviv and Lucien Rebaer chemistry |
| 1:00.3 | at University College London, Anna Kroft, Associate Professor at the Department of Chemical |
| 1:04.8 | and Environmental Engineering at the University of Nottingham, and Mike Murphy, Professor of |
| 1:09.0 | Microdocondural Redox Biology at Cambridge University. |
| 1:12.6 | Nick Lane, can you define what a free radical is? |
... |
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