Summary ☆ Life at the Extremes 102

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Summary ☆ Life at the Extremes 102 Ð ❴Download❵ ✤ Life at the Extremes Author Frances Ashcroft – A Vida no Limite é um relato espetacular da ciência da sobrevivência e dos desafios ue enfrentamos em ambientes altamente hostis em grandes altitudes sob intensa pressão no calor e no frio extremo A VidAshcroft concentra se principalmente na fisiologia seu campo de trabalho mas ponteia a argumentação com conhecimentos e curiosidades de áreas tão variadas uanto medicina história da ciência esporte e zoologia comparada Acrescenta ainda relatos a. Fascinating Scientific findings are interspersed with interesting personal observations making it a fluid read despite being filled to the brim with information However although I enjoyed that parallels were drawn and scientific findings illustrated with examples from the author's personal experience it was clear that unsubstantiated assumptions were being sometimes made For examples it was clear that the author only had observed schoolchildren in the UK when he states that Raynaud's syndrome like chilblains is less common in countries with relatively severe winters likeSweden than in milder countries such as Britain and Italy perhaps because the harsher climate ensures that people take better precautions In Britain for example schoolchildren play outside in winter and are thus chronically exposed to cold Although I'm certain that the first theory is correct in terms of clothing the deduction that British children play outside in the winter than Swedish children would make anyone who has been to these countries laugh out loud After having lived for at least 5 years in each of these three countries I can confidently say that Swedish schoolchildren spend the most time playing outside in the winter and Italian children the least The Swedish saying that there is no such thing as bad weather only bad clothing is known to all Swedish children old enough to go to schoolAs could be expected considering that I bought this book than ten years ago some of the sports nutritional advice is somewhat outdated and newer findings and records are obviously not included Still I think that almost everyone interested in science will find that this provides an enjoyable rewarding and fascinating read

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A Vida no Limite é um relato espetacular da ciência da sobrevivência Life at ePUB #199 e dos desafios ue enfrentamos em ambientes altamente hostis em grandes altitudes sob intensa pressão no calor e no frio extremos na velocidade no espaço Frances. As a Christmas present to myself I decided to read Life at the Extremes The Science of Survival by Frances Ashcroft professor of physiology at the University of Oxford And what a Christmas present it was This book was a hidden gem in the libraryLife at the Extremes is all about the effects of the extreme environmental conditions on the human body including heat and cold height and depths space microgravity and with regards to sport pushing your body to the limitHighly accessible and filled with science this book is perfect for anyone but I would especially recommend this to A Level Biology students like me or those who want to do Biology or Medicine at university The book covers so many aspects of physiology that we experience almost daily in our lives like how we regulate heat and cold the energy demands of speed and stamina and aspects that we do not such as living in microgravity and high altitude etcThe book is divided into 7 sections Life at the Top Life under Pressure Life in the Hot Zone Life in the Cold Life in the Fast Lane The Final Frontier and The Outer LimitsLife at the Top talks about the high life literally It talks about altitude sickness and why it occurs What I love most about this book and especially this chapter is that there is also some history of how these conditions were studiedAltitude sickness is a condition that usually occurs when you're at a high altitude usually above 8000 feet which occurs when you climb up too uickly without allowing your body to acclimatise to the conditions on top of the mountainThis occurs because the air pressure at higher altitudes are lower than at sea level As a result the amount of oxygen we get into our blood is lowered and the body has to acclimatise If this acclimatisation process does not occur the condition can be fatal and there are unpleasant symptoms such as headaches dizziness exhaustion and nausea which take their toll when you're climbing a snow coated and dangerous mountain like the EverestIn the chapter Ashcroft discusses the lungs and the role of haemoglobin in our red blood cells and how this globular protein transports oxygen to our cells The role of the hormone erythropoetin the chemical that stimulates the production of red blood cells is also discussed and it is interesting to note that some athletes used this hormone to improve their performance by using it to increase their red blood cell levels and it is even interesting to note that it is probably of little benefitThe next chapter Life under Pressure is about how humans cope in the depths of the oceans There is definitely a lot science in this chapter especially the physics of pressure which can sometimes be difficult to keep up with however all is explained clearly History about the development of the diving suit is recounted and how the first cases of the bends came aboutThe bends or decompression sickness occurs when a diver who has been at depths of over 10m under water for a long period of time rises uickly This happens because a lot of nitrogen dissolves into the blood under pressure When the diver rises uickly the pressure is suddenly lowered and so the nitrogen can no longer stay dissolved into the blood and so it comes out of the solution to form gas bubbles inside your body and blocks the flow of blood in small blood vessels resulting in joint pain and paralysis especially when the blood vessels to the brain are blocked The phenomenon is similar to the fizzing of a fizzy drink like coca cola when you open a can Carbon dioxide dissolved under high pressure suddenly comes out of the solution as the pressure drops The condition can be fatal due to the lack of oxygen and nutrients provided to the cells and tissues when blood vessels are blockedThe biology in the chapter is incredible fascinating Ashcroft also explains that whales don't get the bends because they limit the gas dissolving into their blood by breathing out before a dive and limiting blood flow to the lungsChapter three Life in the Hot Zone discusses how heat affects the human body and how we sense heat There is also plentiful history about the development of the thermometer Ashcroft talks about how and why we regulate our bodies homoeostasis the processes that occur in the body to keep our body functioning normally Homeostasis is important to keep our body functioning properly and this involves regulating the temperature so that the core body temperature reaches the just right temperature which is important as our metabolism depends on enzymes which work best at the just right optimum temperature This is why when it's too cold or too hot we can die from hypothermia or hyperthermia because cellular activity is affected hugelyThere is also a lot about physiology in this chapter especially about the thergulatory system and how the skin disperses body heat into the atmosphere but the chapter reads well because it is in the form of stories and analogies so it doesn't sound like a textbook As a result it is so easy to become engrossed in this bookLife in the Cold is about life in the cold Frostbite hypothermia and related conditions are explained in this chapter Other animals are also discussed indeed a large part of this section talks about how different animals are adapted to coldness penguins especiallyI think it is amazing how Emperor penguins can coordinate themselves to be in a large group to conserve heat and huddle for warmth facing continuous darkness and temperatures below 70 degrees Celsius Incredible It is also amazing that babies are born with brown fat or brown adipose tissue which have a greater number of ATP producing energy providing mitochondria Mitochondria produce ATP which can provide energy to burn the fat and act as a heater for babies so that they do not suffer from hypothermia Babies have this brown fat because of their larger surface area to volume ratio which means that their rate of heat loss is much uicker than in adultsATP is discussed in detail in Life in the Fast Lane the chapter about pushing the human body to the limits of speed strength and stamina So much information is provided but it is beneficial most especially for A Level Biology studentsI think this is the most interesting section of the book Ashcroft describes how muscle contraction occurs from the triggering by calcium ions to how glycogen stores are depleting turning them into glucose which is used to make ATP to the protein filaments interlocking and breaking bonds and reforming them IncredibleThe chapter also discusses the difference between men and women's physiue and how it contributes to being better in a certain sport For example women tend to have a greater fat percentage than men do so women are often better in long distance swimming where buoyancy is important and men are better in sprinting where as little a ratio of fat to muscle mass is reuired The chapter ends with the thought that although moderate exercise can slow bone loss in older womenThe next chapter The Final Frontier truly appealed to my inner space nerd It is so enthralling to hear about astronauts in outer space taking that giant leap for mankind but it is even engrossing to hear the stories in relation to the effects of microgravity in space Space is the ultimate frontier the ultimate extreme It is a vacuum It is freezing but the ultraviolet rays from the sun would burn your skin To get there you must be accelerated to over 25056 miles per hour subjecting you to extreme g forces and when you're there you exist in microgravity As a result many physiological changes occur such as a shift in body fluidsUsually fluid accumulated in the lower half of the body due to gravity; in microgravity body fluids migrate to the chest and head and redistribute again causing the moon face appearance of some astronauts The heart does not pump as hard due to not having to pump against gravityEuilibrioception the sense of balance can also be damaged Dizziness can occur due to Space Adaptation Syndrome a condition suffered by astronauts in orbit when the state of weightlessness stops their vestibular system from working properly Reduced production of red blood cells bone loss muscle wasting these are all trials and tribulations that greet the brave astronaut in spaceThe last chapter The Outer Limits although not about human physiology is also very fascinating How some microorganisms can grow at 113 degrees Celsius and others can grow at a pH of 2 is incredible And even life without oxygen is possible For certain microorganisms that is It seems so bizarre that oxygen something that we is vital to our survival is toxic to other organismsAshcroft truly amazes the reader in this chapter It is very well researched and has prompted me to do some research myself it turns out that there are microorganisms that have even adapted to build their DNA using arsenic which is toxic to humans Wow Such is the incredible diversity of lifeI cannot recommend this book enough It is a delightful read and it bears witness to the human tenacity Part survival guide part scientific textbook Life at the Extremes should be in the shelves of every armchair adventurer explorer science enthusiast and Biology students

Frances Ashcroft ¹ 2 Read & download

Life at the ExtremesUtobiográficos uma vez ue se aventurou em uase todos esses extremos e inúmeras ilustrações Com texto claro objetivo e descontraído constrói uma narrativa fascinante e faz uma revelação surpreendente do ue o homem e a vida são capazes de suport. I'm going to be such a boss at trivia in my old age So fascinating