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genetic modification can be done with mutations. A mutation is a permanent change in the sequence of DNA. In order to obtain an observable effect, mutations must occur in gene exons, or regulatory elements. Changes in the non-coding regions of DNA (introns and junk DNA) generally do not affect function. Mutations can be caused by: external (exogenous) ...


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Fishers Geometric Model (FGM) is a theoretical prediction about the adaptation process in traits. There are a number of things to establish before attempting comprehend FGM. Firstly, shifts in an adaptive landscape, in natural scenarios, are generally quite small. Because populations have been evolving for such a long time and the small shifts in adaptive ...


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Yes it is. The easiest plant to transform would be Arabidopsis, which can be transformed by agrobacterium using the floral dip method. The process would be as follows: 1. Design a gene sequence you wish to insert into the plant 2. Synthesize (or otherwise acquire the DNA) 3. Insert the DNA into your agrobacterium, at home you would use a cold snap ...


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RNA splicing refers to a certain kind of RNA processing mechanism which leads to the excision and exclusion of some regions of the primary transcript. You should note that this is not the only method by which such a thing can happen; Endo-ribonucleases can clip the ends of the transcript and this happens in the case of tRNA-processing. But as "splicing" ...


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RNA splicing begins with assembly of helper proteins at the intron/exon borders. These splicing factors act as beacons to guide small nuclear ribo proteins to form a splicing machine, called the spliceosome. These animation is showing this happening in real time. see> ...


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No, you don't. Having the DNA in your hand means that you have access to a macromolecule, not more. Think of the DNA as a book (or a library). From holding the book in your hands, you don't know what the content is. You have to actively read the book to get this information. Sequencing a piece of DNA is basically the same. Your readout is the sequence of ...


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This is a technique from the "old time" of genome sequencing. The underlying method for sequencing is the Sanger chain termination method which can have read lenghts between 100 and 1000 basepairs (depending on the instruments used). This means you have to break down longer DNA molecules, clone and subsequently sequence them. There are two methods possible. ...


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There are two good papers on this that I like a lot: Noise in Gene Expression: Origins, Consequences, and Control Cellular decision making and biological noise: from microbes to mammals. I think they can tell you better than I can, but the major other source of noise is extrinsic noise. Extrinsic noise typically is taken to means two things (both of ...


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Let's do your second one first, you want to find the rate of binding: Yes you are right you need to calculate for km I think I found the paper that ties temp into the reaction rate: statistical approach called response surface methodology (RSM) is used for the prediction of the kinetic constants of glucose oxidase (GOx) as a function of reaction ...


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X-inactivation does occur in XXY individuals.  In phenotypically normal XX females, one X chromosome is inactivated.  Which one of the two X chromosomes is inactivated in any given cell is random. Therefore, about one half of the cells should have the maternal X active and the other half should have the paternal X active. XXY individuals show a wide range ...


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If by "consistent" you mean homogenous, the answer is no. Regions conserved among individuals (and/or species) tend to accumulate less mutations (specially avoiding deleterious mutations). Even within a gene sequence, there are conserved regions which accumulate low number of changes, whereas non-conserved regions accumulate many mutations.


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This sounds straightforward when thinking about it but finding hard evidence is not really easy. As this is too long for a comment, I have to put it in as an answer. Just a few thoughts: All enzymatic reactions are of course temperature dependent and usually have a temperature optimum at the specific living temperatures. For yeast this is around 27°C, for ...


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Well, for start, there are "mutational hot spots", regions that are more prone to mutation than others. As for immune system genes, first of all, lung cells and heart cells and retina cells don't need to mutate those genes, because they don't use them. But you are right that in immune cells there is a lot of DNA futzing in the sequences for the heavy and ...


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There are two important terms to note: Sister chromatids Homologous chromosomes. Sister chromatids are visible during most phases of mitosis, but not rest of cell cycle. colchasine is an inhibitor of micro tubules so it prevents the chromosomes from 'liming up" during metaphase hence it arrests at metaphase and the chromosomes are scattered all Over ...


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Epilepsy is a neurological disorder characterized by hypersynchronous discharge of neurons .i.e abnormal electrical activity in the brain. Epileptic seizures caused primarily due to i) inhibition of inhibitory neurotransmitter systems such GABA neurotransmitters or ii) Enhancement of excitatory neurotransmitter systems such as nAchR. These conditions arise ...


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Based on answers and discussion so far and my own searches, I think there is no widely understood and used term for grouping the X/Z and W/Y chromosomes. You could coin your own term or pluck one from obscurity in the literature, however, I think you would probably be better off not doing so and simply writing X/Z and W/Y wherever you need to refer to the ...


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I just tried a search of major and minor sex chromosomes and found a paper here by Judith Mank who refers to the X and Z as the Major Sex Chromosomes and Y and W as the Minor Sex Chromosomes. I will therefore refer to the W and Y as minor sex chromosomes, and will use the term major sex chromosomes in reference to the X and Z. These terms are based ...


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Regarding the meio/majo or micro/macro suggestion, I do not think it is the way to go for the following reasons: Micro and macro-chromosomes are terms already used in species such as chicken whose genomes combine very small and big chromosomes Although this is more the exception than the rule, bear in mind that sometimes the Y chromosome is bigger than the ...


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I think you can safely use the terms heterogametic (Y/W) and homogametic (X/Z) chromosomes, meaning that a heterogametic chromosome is the chromosome which makes one of the sexes heterogametic (i.e. defines the difference between the two types of gametes of the respective sex). These terms applied to chomosomes do have some usage in the literature, e.g. in ...


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Your markers are probably fine, especially because you keep seeing the same allele in multiple individuals. Dinucleotide repeats do not always copy perfectly. More likely, remember that the primers you use to amplify your microsatellites bind outside of the actual repeat region. You could have an insertion/deletion in the region between the primers and the ...


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"Monosomy for the X chromosome in humans creates a genetic Achilles' heel for nature to deal with." The article I quoted1 tackles this issue. It's from the turn of the century, though, so quite old in sequencing/genetic terms, but the science is still sound as far as I can tell. Here's the money quote: Hence, the X chromosome appears to have a lower ...


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Parts of your general idea are correct, others need some refinement. To skip ahead to the conclusion: I'm going to recommend that you read up about linkage disequilibrium. Everything else is background information that will hopefully help you understand why linkage disequilibrium is what I think you're looking for. Background: Meiosis Basics Firstly, in ...


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some number of interstices (spaces between successive loci) get picked and each chromosome gets broken at each interstice. That number is usually around 1. It's not common to have a lot more than that per chromosome. It also seems clear that all interstices are equally likely to get picked. No, there certainly are "hot spots" that are more ...



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