Thursday, September 27, 2012

She sings the body electric

I heard the first ten minutes of this interview on "Fresh Air" and was captivated by the facts and enthusiasm for science that Frances Ashcroft shared. Great stuff for kids to hear. Please give it a listen.

A few sound bites for you:
On the difference between electricity in wires and electricity in bodies
"Bioelectricity is similar but not identical to the stuff that's in sockets. Both are electrical currents, and, in both cases, the electrical current is nothing more than a flow of charged particles. But the stuff in our houses is carried by electrons whereas the stuff in our bodies is carried by ions — salt such as sodium chloride, common salt, in other words, the stuff you put on your meat. The second thing is that the speed is very different. So electricity in wires is carried at the speed of light, which is around 186,000 miles a second, whereas that in our bodies is very, very much slower."

On how electricity drives the way our bodies and bats sense heat
"Whenever you feel something that's burning hot — this is detected by this particular ion channel. It's sensitive to heat. And it fires off a signal that goes up your nerve cells. And it's exactly the same ion channels that are stimulated by chili peppers. So the reason that chili peppers taste so hot is that they stimulate the same ion channel, and the brain interprets them both as the same thing. And interestingly, they have been modified in vampire bats to detect the body heat of their prey. So that's how they can pick up the fact that your big toe is sticking out of a mosquito net, so they can come and suck your blood."

On how science and scientists work
"Scientists are just like novelists in a way. We're all trying to tell a good story that explains how the world works, and we're interested in understanding how it works in exactly the same way that perhaps the early philosophers were. But we have much better tools with which to dissect it and understand it today. And the thing about science is it's always based on the facts. So if facts change and you discover new ones, or many more new facts don't fit the old ones, then you have to change the story. That's how major scientific revolutions happen, as, for example, when people suddenly realized that the Earth goes around the sun. So science is indeed a theory. But I really like what the very famous American physicist [Richard] Feynman said. He said, 'Science is imagination in a straitjacket.' We are constrained by all the things which we already know, so you can't simply conjure a story out of the air. It has to explain all the current facts and the new ones that have just been discovered. And it has to make predictions that can then be tested to see whether in fact that story continues to hold when we know even more information."

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