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2

Here there be monsters The biggest problem with your scenario as presented is that the complementary genes in the female do not go into the "secondary oocyte" but into the "first polar body" ("2" below). The first polar body remains in the perivitelline space beside the oocyte, but it is a tiny thing, generally considered too ...


1

Theoretically? Yes. Very theoretically possible. In practice? It's difficult to isolate the exact daughter cells (sperm) from the same meiotic event, have these cells complete maturation, and only then have them fertilize an egg. Normally you need quite a lot of sperm cells even with in vitro fertilization, but also in principle all you need would be a ...


3

Nothing is 100% precise - any measurement or process allow for some error, the only difference is how often such errors occur (i.e., the probability of an error). These wildely range in biology - e.g., it is about 1 per $10^4$ in HIV replication, but only 1 per $10^9$ for human DNA (due to the repair mechanisms). Note that $1$ in $10^9$ for human DNA means ...


4

First, I think you have misunderstood the concept of sense/antisense. These are defined individually for each gene, with the sense strand always referring to the coding (non-template) strand of a gene, and the antisense strand to its complement, the non-coding (template) strand. So in your plasmid example above, all genes are encoded by their respective ...


11

If you're synthesizing the insert then you just design it with restriction sites that are compatible to the vector. Otherwise, you can design PCR primers that have restriction sites in them. That way when you amplify your insert you'll attach the restriction sites to it. EMBL, Addgene, and NEB all offer somewhat more detailed explanations of this on their ...


2

The standard text-book answer to this question is illustrated by the cover illustration of one edition of, well, the standard text book which I reproduce alongside an image taken from a teaching site of my own in which you can view several different aspects of the double-helix in 3D. [Views of DNA looking ‘down’ the axis of the helix. On the book cover the ...


0

One is tempted to answer that the helicity confirms a higher stabilty in respect to possible forces trying to separate the two strands. However, the logic of teh question (and such answer) is faulty, as it implies that there is a non-helical alternative to double helix, and that the helical form was evolutionarily selected. I doubt that this is the case (let ...


13

Purely going off experience here having used golden gate assembly methods for 5+ years now, there is a definite lack of literature regarding small part assemblies. In my current lab, we use CIDAR MoClo (a golden gate method) and have assembled 100's of constructs successfully with parts as small as ~ 70 bp. However, when we assemble smaller parts we tend to ...


0

As the embryo of a seed typically contains many cells, it should in theory be possible to obtain DNA from a seed without disrupting it (there may be pragmatic issues with protocol, depending on the particulars of the seed). If you have the DNA and each seed has been produced by a separate fertilization event, then each seeds DNA would be unique and it should ...


1

Two highly unlikely, yet possible ways this could happen: One extremely unlikely possibility is that grandmother was born O. Grandmother's current A typing could be the result of interplacental stem cell transfer from bearing an A child and the mother is an XX clone of the grandmother. How similar in appearance are grandmother and mother? A less rare yet ...


2

Summary The systematic chemical names of many important biological molecules are too long to write routinely in full, and in any case were preceded historically by abbreviated forms which generally stressed the distinguishing features of importance to those studying their metabolism. Thus, as the poster points out, a molecule such as dATP (image below) has a ...


-1

Given that your grandmother is type A and your grandfather is AB, there is very small, minute chances that your mother is in fact the biological child of one or both of them. For your grandmother to say that she is 100% your grandfather's child, maybe he had her with someone other than your grandmother, and due to unfortunate events, that woman died giving ...


14

The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles inferred from classical genetics: i, IA, and IB. The IA allele gives type A, IB gives type B, and i gives type O. As both IA and IB are dominant over i, only ii people have type O blood. [1] So from this standpoint, normal Mendelian genetics cannot explain the blood-...


8

I don't have hard data to share regarding you question, but I can provide some anecdotal evidence. I have used golden gate assembly to build hundreds of plasmids using ~20bp annealed oligos, as well as hundreds of plasmids using ~70bp promoter+RBS, 720 bp eGFP, and ~70 bp terminators encoded on plasmids into a ~6kb backbone. In these cases I use 40 fmol ...


5

It may also be worth considering how you are amplifying and isolating your small part. Gel extraction kits sometimes have an optimum DNA size ranges that may prevent recovery. Or if your part is similar to your primer length you may see considerable contamination in your 'purified' product if say the size of a single RBS.


0

Yes, cryopreservation works quite well for many species, including multicellular animals. So you can freeze the ancestor and wait until the descendant is there, then unfreeze them. A good recent example in the news would be the Siberian worms that woke up after being frozen in permafrost for a very long time. Cryopreservation is routine in laboratories, to ...


1

In principle, you can reconstruct 1/2 the genome of each parent. Each of these halves is still a "complete" genome, in the sense that it (usually) contains 23 full chromosomes (there are 23 human chromosomes). Every person has two copies of their genome, one of which is inherited from each parent. I strongly recommend reading about meiosis to learn ...


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