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Terminology is what is holding you back. What chromosome implies depends on context, i.e. is it replicated or not. In Meiosis. Gametes have 23 PAIRS of chromosomes. That means, that while there are 23 different chromosomes they come in doubles/pairs. This is the typical X like shape we think about when we hear chromosomes. Another way, 1 chromosome can ...


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(For the direct answer to your question skip to the end!) Genetic linkage can affect the spread of other genes. The degree of linkage, affected by the rate of recombination between the point (nucleotide, gene etc.) directly under selection and the other point. If the rate of recombination between to given points is low then linkage between them is high and ...


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Genetic hitchhiking / genetic draft From wikipedia Genetic hitchhiking, also called genetic draft or the hitchhiking effect, is when an allele changes frequency not because it itself is under natural selection, but because it is near another gene on the same chromosome that is undergoing a selective sweep. The term "selective sweep" is used improperly ...


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The answer is a bit of a 'yes and no', though mostly 'no. The Y chromosome has very few genes, but arguably the most pivotal is the sex-determining region Y or SRY gene, also known as TDF or testis determining factor. The protein this gene codes for acts essentially as a master switch for male phenotypes by triggering the development of testes in the ...


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Yes, having a Y chromosome does cause specific alterations to facial structure. The Y chromosome doesn't contain much actual genetic information. Most of the information needed to activate the male developmental program (the female one is the default) is in just one gene 'SRT', the other genes on the Y chromosome aren't super important, such that you can ...


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If height was fully determined genetically (and no trait is), then concordance between monozygotic pairs would be almost perfect, modulo some variation due to somatic mutation in early development (e.g. a mutation happens in in cell directly after the embryo splits).


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So the term allele is a broad one, and simply refers to the different versions of any piece of DNA in circulation in the gene pool - it doesn't need to refer to a gene. I can talk about the alleles at a random place in the genome. But if we proceed with your question and ask - 'do nonsense mutations within coding genes also lead to the creation of different ...


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Allele is just a variant form of gene: independent of the final product of protein, so nonsense will also lead to new allele. I will quote Nature Scitable here: Alleles can also refer to minor DNA sequence variations between alleles that do not necessarily influence the gene's phenotype.


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They occur because there is no reason for them to be selected against. Except for a 25% chance of offspring not surviving, in the rare event that the other parent also has the mutation. That recessive, lethal genes can persist in the population is surprisingly one of the reasons that diploid organisms that sexually reproduce are so successful and diverse. ...


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It would be beneficial to a population for a lethal gene to evolve in incestuous situations because genetic diversity is then promoted through natural selection. Genetic diversity is necessary for a species to evolve which would improve the chance of survival.


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Lethal genes evolve simply because of random deleterious mutations and absence of strong selection. Recessive lethal genes Random mutations can make a gene product non-functional or reduce its activity. However, in diploid organisms the other fully-functional copy of the gene can compensate for the non-functional allele. Sometimes both the alleles can ...


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The term sister chromatids refers to the pair of chromosomes which have been produced from a single parent chromatid by DNA replication, while a homologous pair refers to chromosomes which are more distantly related (e.g. those inherited from one's mother and father, which I guess is what you mean by 'male and female chromosome'). So the two options you ...


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This is just loose terminology. By ‘lethal gene’ Dawkins means an essential gene with a mutation that renders it inactive. With a recessive gene, the one ‘good’ copy in the heterozygote provides enough gene-product to allow survival, in contrast to the situation in the homozygote where the total absence of gene-product is lethal. With a rare mutation, the ...


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The accuracy of CRISPR to its target is not necessarily a problem at this time, because scientists have developed a more accurate version of it, CRISPR hf, which has almost no off target effects. Here's a report on a study with a very accurate version of CRISPR


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Repeats aren't the problem with CRISPR. They stop you from editing repeats and repeat-like sequences, but in principle they can be worked around through careful design of guide RNA. CRISPR techniques right now do have problems with off target effects, but these problems may yet be solved. The CRISP/Cas approach to gene editing already has a lot of different ...


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This is not an area I know well, but I'm familiar with a couple of studies that have tried to estimate the heritable (genetic) component of homosexuality in humans. A review paper by Rice et al (2012) points out that: Pedigree and twin studies indicate that homosexuality has substantial heritability in both sexes, yet concordance between identical twins ...


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Another source of developmental noise is due to diffusion. Diffusive processes are stochastic and induce noise in morphogen gradients and results in the concentration as being "jagged". Recent results have directly measured the noise in morphogen gradients of the developing zebrafish. In fact, when you think about the low copy numbers of transcription ...


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The term polymorphism is broad and can have different meanings. Here are your definitions Multiple Allelism: The existence of more than two alleles of the same gene within a population. Polymorphism: the occurrence of more than two distinct phenotypes of a trait in a population. Considering your definitions only, then multiple allelism has to do ...


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Does this mean that the interspecific hybrid is fertile? Yes But is it possible, that an interspecific hybrid is fertile? Yes You might be confused by the idea that by definition two species should not be able to interbreed. If so, then you should have a look at How could humans have interbred with Neanderthals if we're a different species?.


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This is a deceptively and badly worded trick question. Your confusion is because it starts with a mention of RNA polymerase, which transcribes DNA into mRNA, but asks about the protein, which is produced by the translation of the mRNA on ribosomes. The first step in solving the problem is asking what is the sequence of the mRNA produced by the ...


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Relatedness of ants within a colony vary from species to species (as different species may use different mating systems) and from colony to colony. I will consider a basic (simplified) model of a honeybee colony and describe it a little bit to try to address your question. Simplified Model of a ant colony In general, a queen can have several mates. The ...


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I am just repeating @emhart answer but wanted to highlight the semantic. There are several ways an individual can inherit from its parents. Genetics Through transmission of DNA. An acquired trait cannot affect DNA sequence directly and therefore cannot be inherited genetically by the offspring (this sentence is the answer to your question). Note ...


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The primary product of protein coding genes are mRNAs. When we talk about measuring gene expression we want to assay the steady-state levels of a specific mRNA within a cell. This is usually accomplished by starting with a large number of cells and harvesting all of the mRNAs from all of the cells. One way to measure the expression level of just one ...


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According to next generation data: I was never working directly with mRNA but what I got from the bioinformatician was something like this: you extract your mRNA, sequence it, filter it according to the quality & length, assemble it and what you then have is something like "transcripts". Those you are counting: xy of transcript1 & yx of ...


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Yes. In principle you will have a vastly increased ability to customize the boundaries of each protein domain with a primer and PCR based approach. It is not obvious to me that the Gateway Cloning System is required, or necessarily the best choice for this approach, but that is likely subjective. Are you familiar with, or aware of, the efforts of the SGC ...


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Recombination does not make any two genes completely independent because there will not systematically be a recombination event between two given loci (=position on the chromosome). Distance between loci Consider two scenarios that describe the position of two loci on a chromosome. Tightly linked loci Consider two very closely linked loci. Let's say ...


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Normally only one strand of DNA is transcribed. This is possible because for the RNA polymerase to bind and start transcribing the DNA into mRNA (or pre-mRNA) a special sequences on the DNA called a promoter is needed. Promoters will normally only be positioned to allow transcription in one direction, i.e. of one DNA strand. Bacteria and their viruses ...


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If a piece of DNA were to be transcribed on both strands, at the same time, the transcription complexes would collide and inhibit each other, like steric hindrance. If you could overcome this interference and synthesize primary transcripts from both strands, it follows that the two RNAs would hybridize to each other and form complementary RNA-RNA hybrids. ...


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You are trying to work out who your mother's father was. You know that your mother's mother had blue eyes, but your mother had brown eyes. You also have blue eyes. You make an assumption that eye colour is a Mendelian trait, with a dominant brown allele (A) and recessive blue allele (a) such that AA and Aa are brown-eyed, while aa gives blue eyes. To have ...


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One of my potential grandfathers had blue eyes, so if it had been him my mother would have received two blue eyes genes and have blue eyes. No, this does not necessarily follow, because eye color genetics are more complicated than just one dominant-recessive gene. See, for example this article from a someone at Stanford University on How Blue Eyed ...


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On a high-school level you are right. Still, the answer to your question is no. As you may have already noticed, nothing in reality is as simple as schools tell us. Eye colour is generally determined by one gene, but there are other genes which can modify the effect. Think about this question: if there were just two alleles, blue and brown, where would ...


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My intuition would be that this has to do with the neuroscience of social behavior. Many animals, especially those that live and travel in groups (eg. humans), have a great deal of brain "wiring" dedicated to engaging in social behavior with other members of their group. This is an advantage from an evolutionary perspective, since it helps with ...


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In general, point mutations are introduced in the proteins of interest during directed evolution. These can be specific mutations in the active site of an enzyme if you would like to change its specificity towards a new substrate, for example. The point mutations can be introduced with primers when you amplify your gene of interest. However, if you don't ...


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Concise Answer The 5′-UTR region of a eukaryotic mRNA is derived from the RNA transcript of the region of a gene between the transcription start site and the DNA corresponding to the translational initiation codon. It differs from that region of the initial transcript in most cases by having a modified guanosine nucleotide added at the 5′-end in a ‘cap’ ...


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Chortippus parallelus is a common species in Europe that is according to my grasshopper id-guide extremely variable in color. It can be green, brown, yellow and even purple. I can verify that from field experience. Pink however is much more rare, and considered to be caused by Erythrism See https://en.m.wikipedia.org/wiki/Erythrism for explanation and ...


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"To me it seems like both clone based sequencing and shotgun sequencing could have been used together," I believe they were. The public project cut up the genome into BACs and shotgunned every BAC, and then put the BACs together, while Venter used some sequence position information from the public effort to help him place his shotgun pieces. ...


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I do know that the TED Ed episode linked (at 3:50) actually says that 500 million people have myopia or hyperopia, which is 1000 times what the question says, and which seems more reasonable for a world of 7.4 billion people (skewed towards the young).


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Meiosis does not determine sexual form. Eukaryotes use meiosis and fertilization to recombine genes to form new combinations. Meiosis does produce haploid cells from diploid cells, but that has nothing much to do with the sexual forms involved. In the case of the algal genus Chara, the organism's life cycle is entirely haploid except for the ...


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There's two parts to your post that I want to address, the first is the quote (because I want to make sure you understand it well), and the second is about general inference methods for estimating the genetic composition of ancestral populations. The Quote: Selective Sweeps A selected variant that increases rapidly in frequency in the past ~250,000 ...


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Short answer The 5' UTR on the mRNA includes sequence from the Transcriptional Start Site (TSS) to the first exon. Promoters are usually associated with a corresponding TSS. Longer answer In defining a UTR we must consider where transcription begins. Strictly speaking transcription begins at the Transcriptional Start Site (TSS). A useful website for exact ...


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The UTR is the region of the transcript upstream of the starting methionine. The promotor is not itself transcribed.


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There are really two ways to infer past genetics. Sample the past. Only really works if you have well-preserved uncontaminated archaeological samples, but works surprisingly well, considering. The accuracy and completeness goes down fairly quickly as you go back in time but thousands of years to hundreds of thousands of years is roughly possible. You ...


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The methods that come immediately to mind are mostly related to next-generation sequencing. You can do deep sequencing on your sample, which is just increasing the coverage as much as possible to find rare events. You can do RNA-seq to look at the transcriptome, ChIP-seq to look at chromatin modifications, and single-cell sequencing (a form of deep ...



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