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Is there an agreed-upon definition as to how many nucleobases constitute a gene? If not, why not? There is no such definition. A gene is a region of the DNA that is transcribed. Typically a gene should have a transcription start site dictated by a promoter and a transcription stop site marked by termination signals (like terminators and poly-A signal ...


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You call it a thought experiment but something like this has actually been done. Not entirely similar as they don't switch 2, but still they replace a codon. An overview: https://en.wikipedia.org/wiki/Expanded_genetic_code Big thing: in the two articles leading up to this one they replaced all 314 UAG stop codons in E.coli K12 and used the now unused UAG ...


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How are gene size defined? DNA is made of 4 nucleotides A,T,C and G. A series of such nucleotide make up any section of the genome including the genes. The number of nucleotide in a gene is what we call the gene size. Of course, one might discuss on the definition of the exact beginning and end (and methods to determine them) of a gene but this is a ...


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This is in between an extended comment and an answer. What do you mean by "Natural"? The question makes no sense as the term "natural" isn't properly defined. (I am voting to close as unclear). For example, if you go to an area where there is "naturally" a high radioactivity, this will increase your mutation rate. Is this a natural way to change your ...


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I would add this as a comment to your question but do not have enough reputation. A simple look at Wikipedia (which is a very good source for general questions like these) would have provided you with an answer. I just did this to see how long it would take if I did not know the answer. It was about 20-30 seconds. Protein synthesis: Transcription In ...


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Animals can be generated with genetic defects similar to Down Syndrome, but not that exact condition, except in the case of great apes. Down Syndrome is a kind of defect called a chromosomal abnormality, meaning that either there is an extra chromosome or an excessive repetition of the same genes on a particular chromosome. In the case of Down Syndrome, ...


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Hasn’t your question already been answered by those organisms (and organelles) that have a different genetic code from the standard genetic code (originally known as ‘universal’)? Essentially they have performed the experiment for you by developing machinery to decode mRNA differently (transfer RNAs with appropriately different anticodon/amino-acid accepting ...


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On one hand, designing an experiment which would kill (and resurrect) a cell is not possible: once a cell malfunctions, it's likely damaged beyond repair. However, other than that I don't think this experiment kind of cannot actually be done. You would just have to simultaneously expose different cultures (grown in the same conditions) to different inserted ...


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Your understanding of DNA is correct. DNA is a heteropolymer of monomers called nucleotides and each nucleotide is made up of a sugar (deoxyribose), phosphate and a "base" (A, T, G, C). As you already know, DNA is organized as a double helix with the Watson-Crick pairing rules. A chromosome contains a single DNA double helix. Many organisms have multiple ...


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OK, let's set up a specific hypothetical situation so we have some details: A virus (we'll call it Human Nasty Virus 1 (HNV-1)) can infect T cells (a type of white blood cell in the immune system) by binding to a certain receptor on its surface, which we'll call the Nasty Virus Receptor (NVR). Scientists have found that HNV-1 absolutely needs a certain ...


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Genetic information is the heritable information used by organisms to guide their self-assembly. It's why traits can persist across generations. DNA is, by far, the primary material used (by life) to encode genetic information, but it's not the only one. RNA is a pretty common alternative to DNA. If we're looking to Wikipedia, this is actually referred to (...


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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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Interpretation of the question You ask two things: 1. the number of nucleic acid bases that constitutes a gene, 2. (implied) how the size of genes are defined. The first question appears strangely naïve, but the second suggests this may be a misunderstanding. I therefore intend to start there. How are the limits of a gene defined? Genes are defined in ...


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You ask initially about the “sense” and “antisense” strands of DNA. These terms are explained in the Wikipedia reference entitled ‘Sense strand’. This states what you appear to be already aware of, that: “The sense strand is the strand of DNA that has the same sequence as the mRNA, which takes the antisense strand as its template during transcription…” ...


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Seeds are generally made in order to stand dry/cold conditions. I don't see any reason to believe that the DNA got damaged during freezing (that could cause mutation and phenotypic changes). So, if they have germinated, the plants should not be any different from the controls.


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It depends on the animal, some can get it, others cannot. Down syndrome is the result of an extra copy of the twenty first human chromosome. So, it is a rather humanly genetic problem. However, the closer an animal is to humans, the greater the chance of it being at risk of suffering from down syndrome. There have been several chimpanzees found ...


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These terms are quite similar and, for many, confusing: Chromatin Chromosome Chromatid But they are not synonyms. According to "Molecular Cell Biology", Lodish, 4th ed: Chromatin: Complex of DNA, histones, and nonhistone proteins from which eukaryotic chromosomes are formed. Thus: Chromosome: In eukaryotes, the structural unit of the genetic ...



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