HUMAN BODY Life Story movie online

Her eyes will be able to distinguish over a million colours. If she gets married, she'll spend 6,809 pounds on her wedding day. to the same person for the rest of her life. By that time, she'll have walked over 22,000 km and talked for 12 years. It's an amazing list. In fact, no life is an ordinary story. We will each in our time do an incredible amount. And the driving force behind everything we do is the most complicated and mysterious organ in our bodies - it's our brain. This is something I've never done before in my life, and I never thought I would. Simply being is part of a complicated balancing act, the mechanics of which are completely hidden from us. Just as our bodies hide the miracle of everyday life, so they hide from us an even bigger surprise. The Earth was covered in volcanoes, billowing steam and sulphurous water. Had you been standing here, you'd have been present as the story of life was unfolding. Had you been standing here, you'd have been standing by the planet's most advanced life form. In this almost boiling water there are thousands of long, thin strands. They are colonies of tiny, heat-loving creatures: bacteria. The human body is just one branch in the huge, spreading tree of life that grew from those simple bacteria. A new challenge has been met with a new answer. Our bodies, too, face different challenges in life story and we are reworked to cope with each of them. From the moment we are born, we are changing and adapting to life's demands. And every change we make follows a plan drawn up for us by the millions of generations that have gone before. In this series, I'm going to show you the science of these changes throughout life story. They're nurse cells, up to five million of them, ready to feed and nurture the egg. The egg itself is deep within them. This is ovulation. It will happen just 400 times in a woman's life. It is the beginning of the possibility of new life. In a moment the information will fuse together. And the instant that happens the unique inherited characteristics of a new life will be fixed. For nine months, the baby's been fully equipped for life in the warm liquid world of the womb, relying on its mother for food and oxygen. Remarkably, even at this late stage, the heart of the baby is not yet ready for life outside the womb. A special type of fat is concentrated on his back and around his chest. This baby fat can be broken down to release emergency heat. But for the first six months of life, Bob's ability to control his temperature is very limited. But with the larynx so high it can't perform its major function in life - speech. Understanding what motivates others, in fairy tales or real life, seems obvious to us. Adrenalin makes you run faster just for a moment, but the hormones of puberty change your life forever. Not only do they produce the hormones that drive puberty, but they contain the raw material of new life - a woman's eggs. Its lining thickens, ready to be home for a fertilized egg. This is it, ten thousand times larger than real life. But once the sperm factory is up and running, there's no going back. A man will go on producing sperm for the rest of his life. Quite apart from the physical transformation they bring, hormones trigger a much wider change. They influence teenagers' whole outlook on life. With all those hormones wreaking havoc inside us, the body chooses now to confront us with one of life's trickiest challenges. Perhaps it's one of nature's little jokes. Just as we're really growing up, and how we look is as important as life itself, our body starts playing tricks on us. Animals do this to some extent, but the human brain excelled at it. We still use this skill in city life, but in the natural world, you can witness it the way it was originally deployed. Over time, the branching connections between these neurons is strengthened. This is how we remember our family and friends, the important events of our life. Around one thousand kilometres over a lifetime. Whether your hair curls or not depends to some extent on where you're from. Caucasians or white Europeans have hair halfway between the two, so they tend to have slightly wavy hair. White Europeans tend to go grey earlier in life than black or Asian people. Again, it's down to genetics. But another has it that we grow old because of something that is actually vital for life oxygen. We tend to think of oxygen as healthy and essential for life. The end of life comes not as a single quick event, but a slow winding down. It is difficult to say when every cell in the body ceases to have life. You'll journey with me on the road that your body takes. Through dangers. Through miracles. And through time. We'll see the human body in all its forms, fom our beginning to all our ends. Now I'm going to see it in a new light. Come with me. Like most of us at birth, there's really nothing to her. A bit of fat, a little sugar. A bit of protein. She's really just a collection of chemicals. And yet she's the most complicated thing on Earth. During her lifetime, she'll achieve the most amazing things. She'll eat for nearly three and a half years, consuming 7,300 eggs and 160 kg of chocolate. She'll produce 40,000 litres of urine. She'll dribble 145 litres of saliva before her first birthday. She'll crawl 150 km before she's two. Then she'll learn a new word every two hours for the next 10 years. By the time she's ten, her heart will have beaten 368 million times. She'll spend a little over 12 years watching TV. And two and a half years on the telephone. She'll spend two weeks kissing. She'll grow 28 metres of fingernails, and 950 km of hair on her head and more than two metres up her nose. By the age of twenty one, she'll have breathed over 3 1/2 million balloons of air. She'll work for a total of just over eight years. She'll produce 200 billion new red blood cells each and every day. She'll be able to put a name to 2,000 people. 150 of them she'll call her friends. She'll shed 19 kg of dead skin. She'll have sex 2,580 times with five different people. She'll fall in love twice. She'll blink 415 million times. She'll have two children and four grandchildren. When they grow up, only two of her eight great-grandchildren will remember what her name was. In Britain, she's likely to live for 79 years; in France, 82 years; in the USA, 80 years; and in Africa, only 55 years. Despite my brief experience, I can do a bit of it on auto-pilot. Everything that's alive, and some things that aren't, gives off heat. That's what you're looking at now. All your body is burning up energy and creating heat as it goes about the business of being you. But the hottest bit of you is up here. Your brain burns up the most energy in your body, almost a fifth of all the calories you consume. And it uses up almost the same amount whether you're concentrating on something difficult or just wondering whether to put the cat out. Your brain is constantly challenged with its most difficult task: keeping you alive. Right now, there are a few things on your mind. Tonight's dinner, for example. For starters, your brain is coordinating a major haulage operation. Though the route is usually downhill, food doesn't fall to your stomach. When you swallow, your brain triggers muscle contractions. The first scheduled stop is the stomach. It's essentially a biological liquidizer. Its lining is covered in delicate folds which allow it to expand with each mouthful. Inside, a mixture of enzymes and hydrochloric acid start to digest your food. Your dinner's probably still inside. It churns away for about four hours. Soon it will be released into your small intestine, and, at a cue from your brain, bile will be added. This will help you break down fats. You'll be carrying tonight's dinner for about 24 hours. So I hope you liked it. When it does leave you, it will take about 25 grammes of dead cells from your gut with it. But don't worry. You're constantly replacing cells from head to toe. Your brain is managing the body's workforce of 50,000 billion cells. And most of them don't last more than a few years. Cells are constantly dying and being replaced by new ones, up to a billion new cells for old every hour. This means that most of your body is a good deal younger than you are! But these cells aren't replaced and they're particularly special. Each one has a natural tendency to twitch. They're heart cells, and millions working at once is a heartbeat. It's your head that rules your heart, as it's your brain that decides what rate your heart should beat at. The part of the brain controlling your heart is looking after the outside of you, too. Your body must maintain a temperature of 37 degrees Centigrade. And your brain has a range of tricks up its sleeve to do it. This is skin magnified a thousand times. If you look closely, it's covered in holes. They're the openings of tiny ducts, tubes through which sweat can flow. There are about 65,000 of them on the palm of your hand alone. If you're getting too hot, your brain switches on your sweat glands. As the sweat evaporates, it will help cool you down. Should your brain decide that warmth is needed, it has another plan. Goose pimples. They trap warm air near to the skin and so keep vital heat in. So, all that is being controlled from here, inside your head. And don't think you'll get out of all the hard work by nodding off. Even when we're relaxed or asleep, our brains don't let up. This contraption is covered in electrodes, picking up part of my own brain's activity. 128 sensors detect tiny signals emitted as my brain cells fire. This is the pattern produced when I am relaxed. Even without a thought in my head, my brainwaves show I'm busy. The truth is our bodies are always busy. They just don't tell us about it. What we see as the monotony of our daily lives, when it seems that nothing happens, is actually the result of much activity inside our bodies. We're performing thousands of tasks every second of every day. It's the story of how we came to be the way we are. And it is an amazing story. It will change how you think about your body. The way we live, the shape we are, even the way we think, was decided for us thousands, millions, even billions of years ago, when the human body didn't even exist and planet Earth was unrecognizable. Here we are, 8,000 feet above sea level in America's Yellowstone National Park. If you'd been on the planet 3 billion years ago, it would have looked something like this. What's surprising is it's still here today, just like 3 billion years ago. Whilst dinosaurs came and went, and many other species died out, this has survived practically unchanged. This is because their environment has stayed the same. The water comes from deep in the Earth and so is always the same temperature. Just metres away, the environment is very different. Away from the thermal vents, the temperature fluctuates. Billions of years ago, bacteria were living here, too. But as the conditions changed, they changed as well. From one generation to the next, there were alterations. They were almost insignificant, but these tiny changes started an amazing process. Because if you add up enough tiny changes through generations, you get a revolutionary transformation. From being simple bacteria, they became more complicated. Single cells became groups of cells and then early plants and animals. And the changes continued. Dozens of species became hundreds, hundreds into tens of thousands. Parts of bodies were adapted to meet new challenges. Great leaps were made. A fish's fins, over countless generations, developed into legs, and it became a reptile. Some reptiles developed feathers and became birds. 0thers became mammals in every shape and size from blue whale to baboon, every creature we see on the Earth today, including ourselves. All this happened. It's the miracle of evolution. Yet we carry with us the remnants of what has gone before us in our strange past. And there is a place we can go to see just one of those remnants, shaped by one of evolution's truly incredible transformations. It's inside my own head.

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All we need to do is go and find it. This is my ear drum, a thin skin stretched tight across my ear canal. But what I want to show you lies on the other side of my ear drum. This device can take me there. I'm inside a huge magnet with a field strong enough to lift a car clean off the ground. It's a Magnetic Resonance Scanner it can reveal layer by layer what's inside my head. Up until now this has been the forefront of medical imaging. But we're about to take it one step further. By putting the medical scans together, we've created a 3-D picture of my own head, and I can look at any part of it I want to. I can see the muscles that make up my face. My skull. And my own brain. So now I can take you on that journey into my ear in a way that's never been possible before. This time we can fly straight through my ear drum. We're inside my head and at last I can show you what we've come here to see. 0n the right it's my ear drum again. But now we're looking at it from the back. Attached to the middle of it is what I want to show you. It's a bone. Though it's towering above us, it's actually tiny, about the size of a grain of rice. It's the first in a chain of three bones which transfer the vibrations of my ear drum to receptors in my cochlea.

Remarks

They are the smallest bones in my body and they're perfectly engineered to perform their task. Yet these bones will reveal how evolution has transformed us, because they were once something completely different. Let me take you back, even before birth, and the bones will tell us their story. A fetus in the womb, just twelve weeks old, and it's only a few centimetres long. It would fit in an eggcup. Deep inside its head, its ear bones are forming. Now let's look at younger and younger fetuses. Eight weeks. Seven weeks. Six weeks. We are actually witnessing something amazing, because at certain times in this early development, our human embryo portrays the shapes of the embryos of some of our distant pre-human ancestors. If we use the magnetic scanner, incredible detail is revealed. We can see right through the skin at the brain and the spinal chord beginning to form. And the beginnings of an eye behind the emerging hand. Like some of the creatures that preceded us on the evolutionary tree, it has a curved spine and what might be a tail. The cells that will make them are located here - tiny grooves almost hidden behind that hand. Millions of years ago, the embryo of a distant ancestor of ours would have shared with us many of these features. As well as giving rise to us, it gave rise to all sorts of other creatures. In those creatures, these features that we're looking at here have evolved quite differently. We can actually see it happening with the ear bones, because those very same grooves that in us will become our ear bones in this creature become something else entirely. This is the embryo of a fish. Here is its heart and it, too, has a curved spine. And the tiny grooves here, just a fraction of a millimeter long, have evolved to become not ear bones but supports for its gills. So, some time long, long ago, this lot and I shared a common ancestor. But as we evolved, these little bones were adapted for an entirely different job: to become the intricate mechanism of our ears. And our ear bones are not the only things to have been transformed in this way. Such apparent miracles are in fact all around us. It is incredible, and it's incredibly hard to believe, too, because although we've changed so much, we don't actually see any of those changes happening.