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4

I think this analogy is not actually that bad, but you are making some incorrect conclusions from it especially regarding 'junk' DNA and which parts of a repository DNA holds (which shows the limits of analogy!). Think instead of the DNA of an organism as a single local copy of a particular commit. There is no remote to compare to and no list of historical ...


2

Watch out with analogies. Even when they are somewhat helpful, they are only analogies. That being said, unfortunately, your analogy is completely unhelpful! What if DNA is actually like a software source code repository? You know, it has "master" branch - which is most stable and up-to-date version of program but also it has other branches, experimental ...


0

I'm going to re-interpret this question slightly to make it easier to answer: "Why do genome assemblies frequently consist of large numbers of short contigs rather than a relatively small number of long chromosomes (or full replicons of other types)? And how could I make my assembly better?" De novo sequence assemblies (usually) consist of a set of ...


0

No Not all genes are transcribed, repressor proteins and nuclear receptors can bind the DNA preventing transcription of particular genes. Even things like histone regulation can prevent transcription. There may even be epigenetic regulation of transcription. Source 1 Source 2


1

I found at least one example of genes where the same genes and the same alleles exist in both humans and other primates but the frequencies of the different alleles are different in different primate species and those are the genes/alleles associated with the AB0-blood system that humans and other primates share. Citations from this site: Of the Old World ...


5

No single gene determines the height (a polygenic trait) of an individual. In fact, height is coded for by over 700 genes. Also, I'm caught quite off guard by your suggestion that height isn't linked to sex, which is obviously not true. One gene that is associated with a shorter height (to put it simply), ITM2A, is expressed more strongly in women and so ...


0

The correlations you are looking are all based on some unusual and arbitrary subset of the data. The one type of correlation that people generally look at is the one that we call heritability. For a detailed definition of the term heritability, please have a look at this post. In short, heritability (in the narrow sense; again see above link) is the ...


3

Downloading all this using an E-utils search would be cumbersome as you would have to search against multiple databases. For your specific needs, a GTF/GFF3 file would be good. Basically, a GTF/GFF file has genome annotations (positions of features) and includes features like exons, CDS and in some cases even special codons (such as that for selenocysteine). ...


0

You perhaps need to consider that it's not just humans. All mammals have body temperatures in a fairly narrow range - 97-103 °F/36-39.5 °C. Birds likewise have a narrow temperature range, though a bit higher, around 105 °F/40.5 °C. The advantages seem fairly obvious, at least if you've seen reptiles in cold weather torpor. As another answer points out, ...


1

Consider if cavemen would be efficient at defending and fighting each other and predators if they took 15 minutes to warm up from a cold nap before they can start to move. Animals with wider temperature ranges have to maintain many enzyme genes for enzymes that work at different temperatures, and that's inefficient. If an animal is warm, it processes ...


6

What's the benefit of the average human body temperature? It's a balance between preventing infection and not requiring excessive food intake. It is has also been claimed that this is the temperature at which the most essential enzymes are most reactive, without becoming damaged by excess temperature. References: "Mammalian Endothermy Optimally Restricts ...


2

First, let's learn about the vocabulary to describe how living beings deal with their internal temperature with this answer. Now that you have read this answer, you understand that humans are homeo-endo-therms. There are pros and cons of homeothermy. Those pros and cons depend upon the species and esp. upon the type of environment experienced by the ...


-2

The genes associated with people who have more surviving and reproducing children will be more prevalent in the future. If you live in a multicultural society where different ethnic groups have different amounts of children you can get a perception of how the humans in your country will evolve over time. Also if you live in a country where there is a huge ...


0

Statistically, this is that the maximum mean recombination frequency is 50%. Recombination defined this way means that Gene A and Gene B from one chromosome are not 'together' on the same chromosome after recombination. That means that the recombination frequency is the probability of an odd number of recombination events between the loci. If there is an ...


0

Here is a series of articles explaining DNA Demethylation from Sience Direct. In the most broadest of senses, DNA methylation adds methyl groups to DNA preventing the transcription complex from forming and transcribing the gene into mRNA. By demethylating the DNA, it allows the transcription complex to form and mRNA to be transcribed for translation. When ...


0

But the following sites (Nature and Science) use the "silent mutation" as synonymous mutation. https://www.nature.com/scitable/definition/silent-mutation-10 https://www.sciencemag.org/news/2006/12/sound-silent-mutation


0

Preamble My original answer to this question has recently fallen into the third circle of hell because of a contrast I made between physics and biology which seems to have offended some biologists. I shall let that rest, but provide a new answer to make one point that I feel some biology students need to absorb. Answer The use of the word ‘rule’ should be ...


2

Failure to properly separate homologous chromosomes during meiosis, either by including an extra copy of a chromosome or including zero copies of a chromosome, causes gametes that are 'aneuploid', and as a result, a zygote that results from that gamete will have an extra or missing chromosome as well. For humans, most aneuploidies are completely fatal at ...


0

If you allow for the "RNA world" hypothesis, then the minimum number of amino acids needed for life would be zero, because RNA in that context would be self-replicating and would not need proteins (or their amino acids). Since this question was asked in 2012, with respect to modern life on Earth circa 2019, Craig Venter's lab put out a 2016 paper in Science ...


1

1) I'm told that VNTRs are used in DNA profiling. Does this refer to both minisatellites and microsatellites...or just minisatellites? Actually, it refers mostly to STRs. I worked a bit in forensic genetics and we always published works using STRs markers (one example here, there are plenty in the literature). In addition, I would not be surprised if ...


0

The estimate is probably going to depend on the source, but it's generally at least an order of magnitude more than that. Back in 2002, John Moore, an anthropologist at the University of Florida, calculated that a starship could leave Earth with 150 passengers on a 2000-year pilgrimage to another solar system, and upon arrival, the descendants of the ...


1

Different terms in different fields I think that the two concepts are very similar but are used in different fields. The term "modifier genes" is often used in quantitative genetics and in evolutionary genetics while the term "regulatory gene" is often used in molecular genetics. Example of a modifier gene that is not a regulatory gene The concept of ...


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