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1

These two concepts are not mutually exclusive. You have constructed a false dichotomy. Both of these facts are true: The electrons in the pi orbitals of the conjugated double bonds in the planar rings are hydrophobic. The nitrogen and oxygen molecules (either in the rings, or as substituents on the rings) can participate in hydrogen bonds. There are ...


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To fully comprehend the concept of wobble base-pairing we need to consider the nucleotide sequences of the anti-codons in the tRNAs that have to "read" the genetic code when the mRNA is being translated on the ribosome. The nucleotide in the anti-codon's wobble position is, for example, often inosine. Under the rules for wobble base-pairing an Inosine can ...


3

Your claim that "there is a lack of genetic diversity" in mitochondria is not correct. There is no connection between recombination and mutation rates per se. In fact, mitochondria have much higher mutation rates than nucleus and different types of mitochondrial DNA can even co-exist in one organism, a phenomenon called heteroplasmy (which is found at a ...


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Enhancers and silencers are binding sequences for transcriptional activators or repressors, in which case the sequence is often located some distance upstream or downstream of the gene it regulates. See regulation of transcription for information about how these interact with their target genes (through DNA bending, mediator, etc.). A note about enhancers ...


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"Essentially diploid" means that a normal (most common normal) state is diploid, while any other state will be considered rare (can be normal yet) or abnormal or unusual. The "essentially diploid" is in some way a tautologic, since we can say "human somatic cell is essentially diploid" as well as "human somatic cell is diploid" omitting "essentially". But ...


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Gene is usually defined as piece of DNA that produces certain product, be it RNA or polypeptide molecule. In both cases RNA is produced as intermediate or final product. Nature of RNA production from DNA (aka transcription) is such that it requires double-stranded DNA as substrate, that is a continuous polymer of nucleotides. So, only parts of chromosomes ...


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Usually not (as described in the other answer, non-contiguous pieces of DNA are not considered as a part of a single gene). However there are some cases of trans-splicing in which the spliceosome can splice together RNAs arising from different genomic locations. But these are rare and do not have a direct effect on distinct phenotypes such as eye colour, to ...


1

No, a gene is confined to a single chromosome. A gene is characterized by a start sequence in the DNA (among many other things), which indicates that the nucleotides are to be read and transcribed to RNA. This stretch of DNA in the gene is contiguous, although some parts may be skipped in transcription. Because different chromosomes are physically distinct, ...


2

Some suggestions. For identifying function do a homology search. There is little functional annotation of lncRNAs. So homology based information can be obtained only for protein sequences. So you can try these: Check the coding potential. Find ORFs (perhaps set a minimum length cutoff). To be stringent you can also check for Kozak consensus sequences (for ...


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Independent assortment. Mendel showed that his genetic markers for different traits, or phenotypes are transmitted randomly to the F1 generation. This was before the concept of linkage was discovered, so fortunately he selected unlinked genes. Segregation of alleles. The dominant and recessive alleles segregate away from each other when the germ cells are ...


0

You do not need to merge anything. Photosynthesis already includes the electron transport across the inner membrane of the chloroplast (in case of plants) or across the bacterial membrane (in case of bacteria), creating voltage difference between inner and outer side. The only problem, this voltage is relatively difficult to take away.


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we included a script to calculate this in supplemental material http://onlinelibrary.wiley.com/doi/10.1111/mec.13034/full ....single segregating site per locus or up to a maximum of four SNPs, as is expected for short-read genomic data (see attached R script for estimation).


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What you're describing is a phototrophic biofilm microbial fuel cell! They're pretty neat. Essentially the sun powers the bacteria and the bacteria in the anaerobic side passes electrons through the graphite electrode to use oxygen at the cathode. There's another explanation here. You could also "unfold" cyanobacteria and layer them and you'd probably get ...


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HGF is the ligand for Met, which is a membrane receptor involved in multiple transduction pathways. Gene ID 4233 we're looking at a single gene product for MET. If we're just reading through the wikipedia page for c-Met, when HGF binds to Met, it activates the tyrosine kinase activity of Met. Met recruits Gab1, and this complex mediates interactions with ...


2

Units of genetic distance It took me a little while to understand what MU means. I have never seen MU but rather m.u. for map unit, or cM for centiMorgane. Solving the problem This problem got me thinking a little bit. My logic is the following: Probability of being heterozygous at the first locus You cross two individuals (we'll call them individual 1 ...


4

Short answer Human females do not benefit much from an extra cone class, as color discrimination is hardly affected in most tetrachromats. In fact, tetrachromats often show increased error rates in their color discrimination. In dichromatic New World monkeys the heterozygous females do functionally benefit from their extra cone as they gain trichromatic ...


4

It sounds like you have considered most of the obvious alternatives (and thank you for clarifying the question). I suppose the first question in an alternatively spliced transcript with a retained intron is whether the open reading frame of the protein is maintained. If there is a termination codon that now becomes in-frame due to the intron then the ...


1

Allele is a variant form of a gene. How many alleles there are depends on number of copies of the gene and number of variants. In theory you can have 5 identical copies or single copy and single allele (Y-linked genes come to mind). Regulation is very complicated, I'll refer you to reading on recessiveness, dominance. Barr bodies also have to do with ...


1

A flower (or a person) has two alleles for a gene because it inherits one set of chromosomes from one parent and another, comparable, set of chromosomes from the other parent. Hence there are two copies of each gene, and so there are two alleles for each gene.


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Either strand of DNA can be sense or antisense. SWBarnes2 posts that the "transcription machinery will only bind on the correct orientation" and that is indeed what determines which strand is sense. But note his important statement "the sequence is not correct on the anti-sense strand FOR A GIVEN GENE" (my emphasis). As you move from gene to gene, the ...


1

One of the reasons why DNA is double stranded--this means DNA has sense and antisense strands--is to make a copy. During transcription, RNAs are transcribed referring to anti-sense strand sequences--making base pairs with anti-sense strand. In other words, the sense strand does not do anything during transcription.


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The short answer is the transcription machinery will only bind on the correct orientation. The binding of proteins and such to the promoter DNA strand is determined by the sequence of the DNA, the sequence is not correct on the anti-sense strand for a given gene.


0

All of the other answers are basically correct, I just wanted to add that there are some genes which are present in both the X and Y chromosomes, in the pseudoautosomal regions. These genes are inherited in an autosomal manner (hence the name). A male has two copies of each, just as a female would, and can thus be homo- or heterozygous.


3

In XY sex determination systems the females carry two copies of the X chromosomes, thus can be homo- and heterozygous. Males however, carry one X chromosome, meaning that all loci are hemizygous (excluding those with homologs on the X). Under conditions of complete dosage compensation, often through up-regulation of X linked loci, they are effectively ...


2

Reiterating the above comments. Have a look at Tajima's D. It provides an estimate for the number of segregation sites for a population under a neutral mutation model. The general form of the estimation for a diploid population is $E[S]=4N\mu\sum_{i=0}^{n-1} \frac{1}{i}$. Here the mutation rate of is per-genome not per-site, so $\mu=L * 10^{-9}$ where $L$ ...


2

It could be difficult for RNApol to access genes inactivated because inactivated genes are often tightly packed by chromatin. Many genes have enhancer elements(specific DNA sequences) as well as TATA, and transcriptional enhancers, which are proteins, would recognize enhancer elements in a sequence dependent manner and loosen chromatin structure to make ...


1

This is not a answer but rather a very long comment which obviously would not fit in the 600 characters limit of a comment. Welcome to Biology.SE. How to write a good post I think it is not a good habit to write about personal stories on a science site. It makes your post not very attracting to people who could answer. You should also avoid sentence ...


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The fraction of polymorphic sites that exist in a population is dependent on the biology of the organism. For instance, you would expect to find different rates of polymorphism in related plants that have different breeding systems, e.g. in Silene [1]. Past bottlenecks are also expected to decrease polymorphisms [2]. So, the answer to your question would ...


0

When you ask: Is it possible to take out a gene from an organism and put in a totally different one? The answer is yes. Gene knockout technologies are available in experimental scientific fields. You can destroy your target gene by swapping the gene with a drug resistant gene. You can swapping genes using culturing cells, however it would be almost ...


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If you think about it, monarchs must have a pretty strong genetic component to migration since often they only make one round trip at most in a lifetime. But its not as simple as passing a map in the DNA. If a mountain springs up on the route, the 'common sense' of the butterflies are still operational and they will tend to find their way around it. ...


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Qiagen and Life Technologies call it RNA content, total RNA, or total cellular RNA.


-1

No and yes. What you perceive as domestication has a lot to do with intelligence or even social intelligence of animals. Common fish is too stupid (from our point of view), to have any social bond with humans. Mammals are usually much closer and have similar structure of intelligence and patterns of behaviour. That only if you consider domestication as ...


1

Not all animals are equally predisposed for domestication. To be easily domesticated, animal should have: Flexible diet - and not compete with humans for food Reasonably fast growth rate Ability to be bred in captivity Pleasant disposition Temperament which makes it unlikely to panic Modifiable social hierarchy Wikipedia link above has plenty of ...


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The reason that there are no stripes when black and white people get babies is the fact that the number of pigment cells is the same for black and white people. What is different is the amount of pigment produced, and it will be different in the kids as well (lighter than the dark parent, darker than the light parent) See references 1 and 2 for details on ...


3

Skin colour is determined by additive effects. That is, the amount of pigment is determined additively by the genes. For the basic genetics of it I will give a simple example, which is just illustrative and a gross oversimplification, it's probably much more complex (many loci all acting at once). Imaginary example: Suppose skin colour is affected by a ...



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