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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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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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Males have more muscle mass,so they require more blood.Also females undergo menstrution so they lose more red blood cells.


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I would go with NO for the simple reason: For a cell to become malignant (cancerous), cells need to break several barriers. One is to be able to activate telomerase, an enzyme that restores telomeres and enables infinite cell divisions. Another important part is to be able to ignore apoptosis. This is programmed cell death. Specific cell signals lead to ...


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When UV light is on your skin it has to go through the cell membrane and to the membrane of the core. So it looks like that the DNA is protected. I don't understand what you mean by membrane of the core (perhaps nuclear membrane) but yes there is cell membrane and other cytosolic components. You should, however note that not all cells are spherical; ...


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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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Your brain thinks theres a good poosibility that this can work. So it does on many poeple. Placebo effect. Works also for many many ogher things.


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Activating a neuron generally means depolarizing the neuron, sometimes depolarizing enough to trigger an action potential. In general, molecules activate neurons by binding to their cognate receptors in the neuron cell membrane. Sometimes the receptor is, itself, an ion channel. Other times the receptor initiates a cascade of events in the neuron's cytosol ...


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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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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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Depends on the tea, but most tea (unless herbal) contains caffeine, which is a diuretic. This means it dehydrates, and why one might experience drier skin. However, this is not a direct relationship and the actual reason why one's skin might be dry is a lot more complex. However, for a basic answer, caffeine is your culprit.


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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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Question: QuestionWhat is another physical example similar to the laryngeal nerve that refutes the idea of intelligent design and what does it indicate about our past? Dawkins: The path of the human vas deferens is a similar example. from Reddit AMA with Richard Dawkins So (at least) according to Dawkins the path which the vas deferens takes is ...


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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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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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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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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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I am not sure if I can answer the question of why the primary oocyte gets arrested during meiosis (and finishes after fertilization), but the stage of growth the egg is arrested at does vary widely between species; it's not always primary oocyte. This might suggest that the reason is species-dependent. In sea urchins, it's the fully mature ovum that gets ...


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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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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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Seeing how the Ciliary Muscle (FAT/contracted muscle) can cause for loosened eye lense ligaments (near vision) is what you need to grasp. This video Best Shows WHY and HOW the contracted (FAT) muscle produces this: "accomodation" https://www.youtube.com/watch?v=p_xLO7yxgOk When the Ciliary Muscle contract (close vision) the ligaments holding the eye lens ...



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