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Originally Posted by The_Radiation_Specialist
1) I understand different species have different number of chromosomes but what do these numbers actually represent? i.e. What is the significance of Humans and hares having both 46 chromosomes?
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Nothing. Only that human and hare DNA is splitted in as many parts.
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Originally Posted by The_Radiation_Specialist
2) If we found the DNA of, say, Isaac Newton and since thats the code that includes every instruction to build him, would it be possible to make a clone of him with current technology? With hypothetical technology?
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With current technology that is impossible. I guess that by replacing the DNA in a zygote with his a clone might be produced. In reality however that would be impossible even if we had some well-preserved tissue samples. DNA doesn't survive for centuries and it would be useless. Not to mention revived mammoths or dinosaurs.
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Originally Posted by The_Radiation_Specialist
3) How long does it take for the environment to mutate genes so it better adapts to it? Such as some people having light skin due to lack of sunlight in those areas necessary for Vitamin D production. How does the mutation "know" which gene to alter so that the skin becomes brighter?
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Mutation is practically a random process. It absolutely doesn't "know" anything. Vast majority of mutations are irrelevant or even harmful (like genetic diseases for example), but a very few actually increase the fitness of an individual. Such individuals succeed better at reproduction (more of them stay alive long enough to get offspring, or they're more sexually attractive etc.) and the relatively number of offspring carrying that mutation increase in the population.
It has been speculated that the lighter skin may be related to the domestication of cattle in Eurasia; people got the required vitamin D from milk (and developed lactose tolerance in the process; imagine how huge advantage it was to be able to drink cow milk after infancy). In addition, it didn't matter if darker skin "degenerated" as humans at higher latitudes didn't need so good protection against skin cancer.
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Originally Posted by The_Radiation_Specialist
4) Doesn't the "few billion" bits of data that the human DNA stores seem a bit too low? I would imagine there would be way more data on how a human would function. All those cells would need a lot of instructions.
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The DNA is much more than a sequence of nucleic acids. Although chimps and us share almost identical DNA, the crucial difference lies in how different genes are active. In order to truly understand an organism, one has to know how its genes operate. DNA sequencing is needed, but it is far from enough.