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11

This image from the Kahn Academy article 'Overview of transcription' might help: Essentially, the sense/coding strand of the DNA encodes the sequence that is transcribed. The RNA polymerase binds to the antisense/template strand, for which the code is indeed TAC, but when it then transcribes this strand it is again complemented, giving us the AUG that is ...


8

It depends on the regions of sequence homology between the two chromosomes. Crossing over occurs through pairing of homologous regions. If there's a substantial stretch of chromosome without a matching homologous region on its pair, that non-homologous region should loop out and not be involved in crossing over. Crossovers will occur only in paired ...


5

A genomic library is generated for the purpose of encapsulating the full genetic component of an organism. You do this by fragmenting the genome with restriction enzyme that cuts at its recognition sequence. These fragments are then taken and cloned into a plasmid, so that they can then be sequenced inside the plasmid using common sequences that are found ...


5

Short Answer In referring to genes on a double-stranded DNA chromosome (the situation assumed in this question), the general and scientific usage of the term ‘gene’ includes both DNA strands. The practical definition of ‘gene’ has come under scrutiny in recent years for reasons that will be discussed, especially in relation to the ENCODE project. However ...


4

The International Society of Genetic Genealogy Wiki provides the following situations for which siblings may be considered $3/4$ siblings (a coefficient of relationship of 37.5): a man has children with each of two sisters (the children are related as half-siblings and first cousins) a woman has children by each of two brothers (the children are ...


3

Yes. If duplication of the human gene happened after the speciation event, we have multiple orthologues. This is shown in the following diagram from Ensembl as one-to-many orthologue (ortholog_one2many). In the example from the figure, one human gene has two mouse orthologues, but it could be vice-versa as in your case. This is an answer to your general ...


2

You have it mostly right, however, you are misunderstanding what has gone on here a little. The definition from Springer is correct - a targeted gene disruption is a direct replacement of the gene with a non-functional one. However, to do so you also need some method of detecting that your gene disruption worked and will persist. This is most commonly done ...


2

I think that this question cannot be quantitatively answered, because the baseline "non-disease" state is not well defined. Let's take as a starting point the example that you gave, of sickle cell disease. It turns out there is not actually a single mutation that can lead to the disease, but a number of different mutations. A person with only one ...


2

Like @mgkrebbs commented, the left poster shows a total of 8 chromosomes, but only 4 pairs of chromosomes. I would dare say that you are right and that the poster is wrong. The left has 8 chromosomes, and 4 pairs of chromosomes. The right has 4 chromosomes, and they are not paired up, so the number of pairs is insignificant.


2

A repressor inhibits transcription, thus one expects low transcription when the repressor is present. Thus, if a protein acts as a repressor when it binds arabinose, then when arabinose is present the protein will inhibit transcription. In the typical synthetic case of AraC and pBAD, AraC+arabinose does not act like a repressor, but an activator of pBAD. ...


1

No it is not possible, sperm are missing most of the biochemical machinery need to produce a embryo, sperm have most most of their functional components to make them lower investment and faster. Sperm are lacking several important organelles, including the most important ribosomes. They are not fully functional cells. https://www.ncbi.nlm.nih.gov/books/...


1

Well, it would be difficult from specifically sperm, but if you mean from two members of the same sex -- two men, then the answer is yes. Yes it is (or, rather, will be) possible. Already, it has been done in mice (new baby mice were born from both only mothers and also only fathers): https://www.cell.com/cell-stem-cell/pdf/S1934-5909(18)30441-7.pdf In ...


1

I don't think it is possible. There is a lot happening to the DNA of the sperm and the egg after fertilization, and just mixing the DNA of two sperm or two eggs would not achieve that. Also, a YY embryo would not be viable because the X chromosome contain vital genes that Y does not. That's why there are people with 1X but no one with 1Y.


1

Here's a hint: you're right about 0.01 being the recombinant (crossed-over) double homozygous recessive offspring. I think you're forgetting that each offspring contains 2 gamete haplotypes, and so predicting the percent of offspring with a given genotype involves multiplying the frequencies of the individual gametes that produce that offspring. To calculate ...


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