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It depends, but you're going to die. Specifically, it depends on how fat you are. Even Andreas Munzer is going to die. At only 3% body fat, burning all his fat (9kcal/g) would "only" increase his internal body temperature by 270 degrees C. Factoring in the energy required to boil off his body moisture and adding in body heat leaves Andreas at ~200 C or so ...


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It is yet to be discovered by scientists. But there is a new study that finds that brain cells called astrocytes supply the urge to sleep by releasing adenosine a chemical known to have sleep-inducing effects. The chemical accumulates in the brain during waking hours, eventually helping to stimulate the unique patterns of brain activity that occur during ...


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For skeletal muscles, you'll find a discussion in the Physics SE: http://physics.stackexchange.com/questions/1984/why-does-holding-something-up-cost-energy-while-no-work-is-being-done To make things short: while holding a position, muscles need to maintain a given length. However, internally, the muscle looks like a collapsible array of filaments, with ...


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1) Yes, most cells in the body derive energy from oxidative metabolism, unless oxygen is not available for some reason. There are some exceptions, for example red blood cells lack mitochondria and so have no respiration, and various types of rapidly proliferating cells such as activated immune cells have high glycolysis and lactate production (for reasons ...


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What you're describing is a phototrophic biofilm microbial fuel cell! They're pretty neat. Essentially the sun powers the bacteria and the bacteria in the anaerobic side passes electrons through the graphite electrode to use oxygen at the cathode. There's another explanation here. You could also "unfold" cyanobacteria and layer them and you'd probably get ...


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You should note that even in pure mechanical examples, the energy consumed may not be equal to work done because some energy is also used up in countering the frictional force. In your example you consider an object kept on a wooden table and in this case the weight is balanced by the reaction force by the table. You have not considered the material ...



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