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Only about 5–6% of triglyceride (fat) can be converted to glucose in humans. This is because triglyceride is made up of one 3-carbon glycerol molecule and three 16- or 18-carbon fatty acids. The glycerol (3/51-to-57 = 5.2–5.9%) can be converted to glucose in the liver by gluconeogenesis (after conversion to dihydroxyacetone phosphate). The fatty acid ...


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Your question is very awkward. Let's define Tea as boiling leaves in water. At the end, you remove the leaves and drink the flavoured water. At this point, the "tea" is still very much water - as in tea is water with dissolved chemicals from the leaves. Note, the word chemicals is not to be interpreted in a negative way because everything (including water) ...


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As you suspected, hemoglobin is the reason why O$_2$ and CO$_2$ in blood are expressed as a pressure (mmHg) and not a concentration. Most of the oxygen in blood is bound to hemoglobin; the concentration of free oxygen in plasma is low because oxygen does not dissolve well in water (which is of course the reason why hemoglobin exists in the first place). ...


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This is a very general answer to a very general question. So, in general, cancer occurs when cells stop behaving as they are supposed to. Your body is made by something like 200 different kinds of cells (epithelial cells, neuronal cells, blood cells and so on) working together to maintain the body's functions. If many of those cells stop doing what they are ...


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Yes, there is something like an "odor afterimage", at least in rodents. This is the paper: http://www.pnas.org/content/110/35/E3340.abstract But have in mind that this phenomenon is quite different from visual afterimages. First, it doesn't depend strictly on "adaptation", because adaptation is a property of the sensory organ, not of the brain. Second, ...


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You asked three questions here, so I'll answer them one by one. Yes, you can survive with glycogen as the only source of carbohydrates, assuming that you also take other nutrients like proteins, fats, vitamins, etc. also because carbohydrates cannot supplement all of them. See this article: There are three macronutrients: carbohydrates, protein and ...


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This is a reasonable question, and I was surprised to find that official information on whether Aedes aegypti is present in NYC isn't very clear. I personally would have thought that NYC was quite far beyond the range of Aedes aegypti (the 'yellow fever mosquito', believed to be the main vector of Zika virus in the ongoing emergence event in South America), ...


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There is a difference between animals in their requirements for amino acids. For example, cats need high amounts of taurine (and can't make it) and when fed diets lacking enough can go blind. This is why vegans trying to feed vegan diets to their pets can be very bad for the pet. Animal proteins have sufficient taurine for the cat. However, the meat of a ...


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UV Rays kill the cells by damaging the DNA. UV lights do not disrupt the cell membrane. If a cell is exposed to UV light, it creates THYMINE dimers (bond). Thymine dimers are the actual disruption in the kinks of DNA. UV exposure to skin is proportional to the cell damage. P53 is a gene product which takes care of fixing cell damage. However it has a ...


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By the ideal gas law, PV = nRT, you can find pressure by dividing both sides by volume, P = nRT/V. Since R is a constant, and you can usually assume T isn't changing very quickly for biological systems, you can pretend P = n/V, which is moles per unit volume, analogous to concentration. The reason the units are written in pressure is probably because gases ...


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It depends on the size and the location. After both world wars plenty of people had odd bits of shrapnel wandering about inside them for years, because it would be too difficult or dangerous to get it out. We had a dog who carried a few shotgun pellets inside her, shallowly enough for one to feel one of them under her skin. No point in subjecting the dog to ...


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The problem with odors is that no known odorant hits only one olfactory receptor. A saturating concentration of compound X for receptor A might be saturating another receptor B, but not receptor C. If you now decrease the concentration, receptor A is still saturated, receptor B is only partially activated and receptor C is not activated at all. Since smell ...



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