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"1.5 g·kg body mass⁻¹" can be equivalently written "(1.5 g)/(1 kg body mass)" or read "1.5 grams per kilogram body mass". So, a 87 kg person would be given 130.5 g of alcohol. The units work out as: (1.5 g EtOH)/(kg body mass) * 87 (kg body mass) = 130.5 g EtOH That is, you have (kg body mass) in the numerator and denominator, ...


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No it is not possible, sperm are missing most of the biochemical machinery need to produce a embryo, sperm have most most of their functional components to make them lower investment and faster. Sperm are lacking several important organelles, including the most important ribosomes. They are not fully functional cells. https://www.ncbi.nlm.nih.gov/books/...


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Well, it would be difficult from specifically sperm, but if you mean from two members of the same sex -- two men, then the answer is yes. Yes it is (or, rather, will be) possible. Already, it has been done in mice (new baby mice were born from both only mothers and also only fathers): https://www.cell.com/cell-stem-cell/pdf/S1934-5909(18)30441-7.pdf In ...


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Except in three specific areas (olfactory bulb, dentate gyrus, SVZ) where neurogenesis continues to occur in adult organisms, it is virtually absent from everywhere else, including the cortex. However, there have been many reports that the grey matter of the cortex, i.e. the zone where cell bodies and their processes reside, can enlarge. Cortical expansion ...


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No one seems to be able to decide whether this question is worth answering or not, I will put one down just to bring closure, summarizing some of the discussion in the comments. I think that the question merits answering because the genetics community honestly hasn't done a good job of messaging on this topic. It's a little involved, so I'll break it into ...


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I don't think it is possible. There is a lot happening to the DNA of the sperm and the egg after fertilization, and just mixing the DNA of two sperm or two eggs would not achieve that. Also, a YY embryo would not be viable because the X chromosome contain vital genes that Y does not. That's why there are people with 1X but no one with 1Y.


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i know there are differences. My question was maybe a bit unclear. I didn't want to ask why there are teeth instead of bones, but why there are multiple teeth instead of one large spanning the entire jaw. Besides, parts of teeth (dentin, cementum) are not that different from bones. I never questioned the presence of the harder parts (enamel). For one thing, ...


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It also has some advantages, although some of these have been mostly lost in humans. In sharks for example teeth get continuously replaced, so losing one is much less of deal for them. This true in reptiles too, e.g. a lowly gecko can have 1,000 new teeth their lifetime. (The more technical term is polyphyodont.) It is somewhat of a mystery why mammals lost ...


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