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The Cell - The Hidden Kingdom (Part 1/6)

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What is life? Where does it come from? These are questions that have puzzled human minds for thousands of years. And yet it is only in the last couple of centuries, Take me for example. How is it that I am alive? I can show you what I consist of, the chemicals that make up a standard issue human. You need 18 kilos of carbon, a small canister of nitrogen, 50 kilos of water, enough phosphorus to make 2000 matches, the same amount of iron as a small nail Chemically the two sides are identical. But biologically we are completely different. Obviously, I am alive. And the difference is that these exact same chemicals are organised into cells. 60 thousand billion tiny, incredibly complex structures, that make out my body. Quite simply: We are cells. Every time we breath, we move, we think, cells do the work for us. Like all biologists - the more I find out about them, the more they amaze me. The idea, that all living creatures from amoebas to humans are made up of cells, is the cornerstone of biology. It's the theory of everything. Yet the story of how we came to understand the cell is rarely told. It's a fantastic voyage delving deaper and deaper into an almost magical, unseen world. It's about nothing less than unlocking the misteries of life itself. And for me the story of the cell is the most powerful story in science. Cell: The Hidden Kingdom My starting point is September 1674 and the Royal Society of London. A misterious satchel arrived at this club for gentlemen scientists. It had taken five days to get here from Holland across the North Sea by ship, and then by horseback rider. The package came from a man who had built the world's most powerful microscope. A microscope which revealed a hidden kingdom nobody had seen before. The secretary of the Royal Society opened the satchel. In it there was a long letter in Dutch with the discription of something truly extraordinary. Tiny animals, that pirouetted and swam like eels. And so small according to the author, that you could fit a million of them on a single grain of sand. So, let's have a look. These are the letters. You can see the date 1674 at the top. Written in Dutch. I don't speak Dutch, so I can't understand that. There is the signature, that of sender Antony van Leeuwenhoek. And the drawings came in later letters. You can see these crazy tiny creatures. This one here has got a little dotted line to indicate the movement. Here it is spinning around. So, picture the scene: these guys at the Royal Society, the stuffy old scientists, never seen anything like this before and yet suddenly this letter comes through from Holland with these totally alien creatures. Not only looking really weird, but also so small that they couldn't even see them. It must have been just completely amazing. Did they even believe that these were real? The fellows of the Royal Society did have their own microscopes, the device had been around since about 1600's. But they had never seen the tiny animals van Leeuwenhoek claimed to have found. Quite frankly they suspected this unknown Dutchman must be crazy. Antony van Leeuwenhoek came from the markettown of Delft. He wasn't a scientists at all. In fact, he was a linen merchant. Drapers like van Leeuwenhoek inspected their cloth with magnifying glasses. And Holland had pioneered their manifacture. They are still used today. Here. Look! This... that's maybe nice to show. This is a 17th century napkin. Shall I show you how big they were in those days? This is actually it, from 17th century? This is not a replica? No! This is real 17th century napkin. Huh?! Look! Oh, that's huge! Yes, that was huge. - Were they particularly messy eaters in the 17th century? - Yes, we think so. But they are not. Look! That's like a tablecloth! Yes! But it's only a napkin. Did they thuck it into a... ? Sometimes, but you'd have to put it on your lap of course. Oh my god! I'm sorry, I'm being slightly disrespectful for a 300-year-old piece of cloth. And how do you look at the quality of the cloth? Well, when I want to look the quality quite good, then I use a loupe and I look through it and... Look this is a very old loupe! So, this is a loupe. Which is the same word in English. It's like the watchmakers use. But basically it's a magnifying glass. Ok, magnifying glass. Yeah. And you can look through it, and when you look through it you can count the threads, you can see the threads from the napkin quite good. Can I have a go? Yes, you can have a look at the quality. Thenk you! So, you pull it up and then it comes into focus... And there you go! There you can see every single thread, every single stitch. It's amazing! You can really see the pattern. This is basically exactly the same technique that van Leeuwenhoek would have done in the 17th century. Yes! Yes... van Leeuwenhoek became obsessed with lenses. A sort of a lens geek He turned out to be the best lens maker there was. He used delicately crafted lenses like these in his own unique viewing machine. This is a replica of van Leeuwenhoek's microscope. Look, how simple it is. It is just a piece of brass, it's got one tiny hole with a lens in it, which is probably a 1 mm across. Yet, this is the gadget, that transformed the way we see the world. A tiny lens. Yet, more powerful, than any other. van Leeuwenhoek knew, that it's the curvature of the lens, that bends the light passing through it. So, making the object being observed.. here it's a flea... appear larger. And because van Leeuwenhoek was a master craftsman, he could curve the lens more, than anybody else. Almost to the point it was spherical. This allowed him to magnify objects up to 500 times. Noone would make a more powerful microscope for over a century. So, he now had the technology. But what did he look at? He went from linen to fleas, to the sting of a bumble bee. In fact, pretty much anything he could get his hands on. And one of the things he looked at was water. He'd noticed, that in a lake near Delft the water changed colour with the seasons. And he figured, that there might be something in the water, that he could discover. Many of the fundamental breakthroughs of science seem so simple, so absurdly simple. But we shouldn't forget, that until van Leeuwenhoek noone had the curiosity to find that what might be lurking in the water. He raced home to take a closer look with his microscope. The man, who is going to help me study the water is Hans Loenker. He keeps the spirit of van Leeuwenhoek alive by making replicas of his microscopes. To grind a lense Hans needs no special glass, just the shard from the old jam jar will do. The only way to get enough curvature in the lens is to make it tiny. This was van Leeuwenhoek's secret and it requires great skill and patience. van Leeuwenhoek built a staggering 247 microscopes, a new one every couple of months for over 50 years. And told nobody how he made them. We've placed a drop of my lake water onto a slide, that slots into the device.

Video Details

Duration: 10 minutes
Country: United Kingdom
Language: English
Producer: BBC Four
Views: 5,717
Posted by: vallisso on Oct 28, 2009

Episode 1 of 3

Dr Adam Rutherford introduces a new three-part series that tells the extraordinary story of the scientific quest to discover the secrets of the cell and of life itself. Every living thing is made of cells, microscopic building blocks of almost unimaginable power and complexity.

The first part explores how centuries of scientific and religious dogma were overturned by the earliest discoveries of the existence of cells, and how scientists came to realise that there was, literally, more to life than meets the eye.

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