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You must tell facts from fiction; viruses need living cells to replicate, because they do not have the molecular machinery at hand to generate energy and construct building blocks essential to life. So no, viruses cannot bring back the dead or revitalize dead cells. The thing that comes close to it are zombie ants. These ants have been infected by a ...


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Short answer Between 62,000 and 63,500 feet (18,900 and 19,350 meters) blood begins to boil at body temperature. This altitude, referred to as the Armstrong limit, is generally considered to be the absolute limit compatible with life. At this point, humans cannot survive without pressurization measures. Background Atmospheric pressure drops at higher ...


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Note: This answer is a complement to @Christiaan's answer, and is partly reusing stuff from this related answer. Since you are specifically asking about viruses, I thought that it might be interesting to mention that similar behaviour changes as those mentioned for fungi can also be caused by viruses. See e.g. this quote from Roy et al. (2006): In ...


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We don't actually know. But these two theories are strong candidates: Sleep 'cleans' the brain of toxins. Metabolic waste products of neural activity are cleared out of the sleeping brain at a faster rate than during the awake state. This finding suggests a mechanistic explanation for how sleep serves a restorative function, in addition to its ...


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Crossing over primarily happens because of homologous recombination (HR). From the molecular point of view, it can happen between any homologous regions and it is not necessary that an entire allele has to be crossed over. During the process of HR, a DNA double strand break occurs. This is followed by resection (exonucleolytic degradation of one of the ...


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You don't smell carbon monoxide in cigarette smoke. It's odorless. (And not exactly the part of cigarette smoke I would be worried about.) You smell the other components of cigarette smoke. Which are not odorless. Holding your breath and getting out of the smoke seems the way to go. Even better would be exhaling, then holding your breath until you are ...


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The catalytic domain is roughly referring to the same part of the protein as an active site and may be used interchangeably in some circumstances: See here, where "catalytic domain" redirects to "active site." There is, however, a difference: From a free online medical dictionary: active site: the place on the surface of an enzyme where its ...


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There is a large amount of variation in the distribution and number of chiasmata or crossing overs (COs). The total number of chiasmata per cell can vary within the same organism. Where chiasmata occur along the chromosome is also not consistent cell to cell. Hotspots are 1-2kb regions that experience elevated recombination compared to neighboring genomic ...


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Blood pressure is mostly dependent on the height from the heart. Therefore, if it is below the heart it will have higher blood pressure and if it is above the heart it will have lower blood pressure. Here you are asking from two parts of body that have same height as the heart, so they will have approximately the same blood pressure. For more see: ...


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Welcome to Biology.SE Issues with the question It is impossible to correctly answer this question as the phrasing is so fantastically unclear, wrong and misleading (no offense, really). I will give a few points here that may help you but the only thing you can really do to answer your own question is take some time to follow an introductory course to ...


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There is a lot of confusion and conflicting / imprecise definitions of these terms. It's biology after all :) A mitogen is an agent that causes a cell to enter mitosis. This definition is pretty clear, and there is a good consensus about it. (Well technically, mitosis is not the same as cell division, but we will gloss over this distinction.) The term ...


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You can find a great article about this here. basically, these two groups are very similar in their effects, however they work through different pathways. Mitogens directly promote cell to get through G1 checkpoint through highering the activity of cyclin D/cdk4 (the complex needed to get through the checkpoint.) and according to the article above, also ...


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The vertebral column is a bony, segmented structure that supports the torso/head and thorax. The spinal cord is a bundle of nerves that runs inside the structure of the vertebral column. So - they run together, but are completely separate.


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According to the CDC the zika virus persists in the blood for around a week. Zika virus usually remains in the blood of an infected person for about a week but it can be found longer in some people. - CDC I can't find much information on how long the Zika virus specifically can persist after recovery, it seems unknown just now. However, it is advised ...


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Though we might pray that humans are never manufactured in a lab, it's a stretch to say we "will never be able to make a human being in a lab." There was a time when medical science was viewed as witchcraft. Centuries later, people scoffed at the idea of organ transplants. Today, science has gone far beyond those milestones. Scientists have probed the ...


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Hashimoto's Thyroiditis is an autoimmune disorder where autoreactive attack on the actual thyroid tissue results in hypothyroidism. Pyzik et al., 2015, provides a good review of what we know about HT. The prevailing theory is that nonspecific infection can induce HLA expression on thyroid cells through the action of interferon gamma. HLA is an ...


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Stretching the limits of what is known a bit, there is an interesting example of a phage (virus that infects bacteria) infecting a photosynthetic bacterium in the ocean that deserves mentioning. What is amazing here is that the phage has certain genes that are required for photosynthesis within its genome. Why does it have these? The phage extends the ...


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The term noise can mean a number of different (more or les related) things is used in a number of different fields such as signal processing, psychology and statistics. Outside of its context, it is impossible to say for certitude what you professors were referring to. The quotations below come from wikipedia > Communication noise, wikipedia > Statistical ...


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Based on Figure 11 in the original publication (scale bar = 10 cm): The anteroposterior length of the skull should be about 16.3 cm. I just printed out the figure and did the conversion. So check that your 3D printing software estimates a little over 16 cm for the length from brow ridge to occipital. The full reconstructed skull will be longer of course, ...


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From my research, I can deduce that the cranial volume for males is 560 cm3 (34 cu in) and 465 cm3 (28.4 cu in) for females Note: These skulls are approximately half the volume of modern human skulls average Homo erectus skulls are 900 cm3 (55 cu in) I don't think you would need the area for 3-D printing, but you can use the volume!


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ATP burned per minute is not a useful number because the turnover is so high. 2000 kcal/day is dozens of kilograms of ATP so obviously ATP is turned over more than once a day, but there's probably more than one molecule of ATP being passed around between all the ATP synthases. This blog claims 250 grams. Taking the estimate of ATP concentrations(1-10 mM) ...



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