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I will clarify your question a little. We start with two men, Dave and John. We know Dave and John are related, either as brothers, or parent-child. Can we use genetics to work out their relationship? If Dave and John are brothers they will have the same mtDNA, the DNA in the mitochondria, because mitochondria are maternally inherited. They should have the ...


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Most cells in a human body contain a complete set of the genome, which is two sets of 23 chromosomes. Having two of each chromosome is called diploidy. Within an individual human the DNA is approximately identical in every cell. Different cells are produced by differential use of that DNA: certain genes are more (or less) highly expressed etc. You ...


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Yes, primitive earth was more exposed to radiation as a result of the Earth not having gaseous oxygen during the Hadean eon (which was formed after the oxygen catastrophe as a by-product of cyanobacteria's photosynthesis), which could form ozone and the ozone layer. As a result of the absence of the ozone layer, ultraviolet radiation would not have been ...


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Well, Mitochondrial DNA CAN be linear (in some organism), see the wikipedia page on this In most multicellular organisms, the mtDNA - or mitogenome - is organized as a circular, covalently closed, double-stranded DNA. But in many unicellular (e.g. the ciliate Tetrahymena or the green alga Chlamydomonas reinhardtii) and in rare cases also in ...


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BWA-mem (like most aligners), takes a normal single-stranded fasta file (I've never seen one with both strands listed) and aligns to both strand.


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It is all explained here in Wikipedia. If you want to make a 3D model of your own, you can use two pieces of tygon tubing (like the rubber hose for a Bunsen burner), that are both circularized and attached with connectors that can be opened and closed--that lets you simulate nicking and re-sealing the strands.


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It is all explained here in Wikipedia. You are referring to Watson-Crick base pairs in the B-DNA structure.


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There are two factors that involve the ability of enzymes to process RNA. 1) Structure see wikipedia 2) Binding affinitya Let's take a look at the splicing process: The active 'sites' (GU,A & AG) need to be in spatial proximity (point one), and the enzyme needs to be able to bind there, aka forming hydrogen bonds with the nucleotides, which is mostly ...


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DNA will be never replaced (unless you are speaking about something, where DNA might be only trash, like in the case of blood transplantation or in the case when "organ" would be slowly replaced itself by host regenerative power and "organ" transplantation would be only something temporary, but then we are probably speaking about wider definition of organs). ...


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DNA strands always have one 3' end and one 5' end (since each nucleotide has one of each and a strand is formed by connecting the 3' side of one nucleotide to the 5' side of another nucleotide). In a double helix DNA molecule, the two strands run in opposite directions. The Pearson Education diagram in the post you referenced has one pair of the strand ...


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A single, unwound strand of DNA runs 5' to 3', the video is correct. When wound properly, the strands run in reverse directions, 5' to 3' for the first, 3' to 5' for the other. That diagram is not helpful, though the post itself is quite good.


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I believe the reason you are having trouble understanding the concept is due to a poor usage of colors in the diagram. Don't focus on the colors, but on the concept. It's the same for both replication events. Each strand of a double helix is used as a template to make a new complimentary strand, giving rise to two new DNA helices from the original. In each ...


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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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Well, the oldest intact DNA found is actually 419 million years old, and it belongs to (not surprisingly) bacteria. Samples were extracted from surface-sterilized salt of different geological ages (23, 121, 419 million years of age, MYA). But as you mentioned, these are fragments. Studies on the half-life of DNA suggest that even under ideal circumstances, ...


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The Stanford article that you read is correct, in the sense that telomeres do not need to be completely removed by cell division before deleterious effects occur and cells start undergoing senescence. This Nature article describes an experiment in which the minimum length of telomeres (beyond which chromosomal fusion occurs) was determined: The ...


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Although this is theoretical a problem, in fact it isn't one. Lets do the calculation around it. EDTA complexes equimolar amounts of bivalent cations (e.g. Magnesium), so 1mM EDTA will complex 1mM Magnesium ions. Lets assume that the PCR reaction contains 2mM Magnesium. A typical PCR reaction I do has a total volume of 25ul and contains 1ul DNA template in ...



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