CharonY

This is basically based on the assumption that each point on the chromosome has the same chance of a crossover event (which is not true near the centromer). Hence, if you look at a longer stretch, the overall chance of a crossover occurring is higher than within a shorter one.

Well, technically H1N1 serotypes have been around for longer. Just not the current variant It is likely that they may use the current pandemia as an additional sales boost, but to be fair the article is not very specific about what the claims of the manufacturers really are.

It depends on the virus and of course, the length of the heat treatment. Literature values (known to me) vary widely between 45 to 100° for a few seconds up to an hour. Most widely actually 121° C is used. Theoretically you can go higher and in some instances it actually makes sense. In most cases, however it is sufficient to ensure proper sterilization. This particular value has probably been established as a reference value for industrial/medical sterilization protocols.

Some update http://blogs.sciencemag.org/scienceinsider/2009/10/unrevealed-anal.html

Wait a tick, I may have misunderstood your question. Are asking whether several subunits (i.e. protomers) are needed? The latter is dependent a bit on what model for allosteric inhibition is used.

Note that bacteriophages can only pack a limited amount of DNA. If they accidentally put host DNA into their capsids, they lose some of their own. So if they infect the new cell they inject their original host's DNA instead of their own. Without their own DNA, however, they cannot hijack their new host's cellular functions.

The nucleus possesses porins (essentially proteins that form a channel) that are large enough to let nucleotides pass. IIRC there was no difference in nucleotide concentration between between nucleus and cytoplasma, further indicating free diffusion.

Not quite, for DNA synthesis deoxy-ATP (and the respective other nucleotides) is used. Also ATP-dependent energy transfer is normally limited to a single phosphate residue (i.e. from ATP to ADP). Whereas during DNA polymerization PPi is removed. But yes, the principle is very similar.

In fact, Paul Davies, a Templeton award winning physicist argued that there may be life on earth based on different properties but biologists are too focused on DNA based lifeforms to recognize them. Not that I would be inclined to agree, but it highlights that this is an ongoing discussion (with different levels of quality, of course).

The nucleotides hang around. Not the pure bases. Also remember that the volume is rather low.

Actually it is easy. You have to think more in terms of mechanism. On which part does a competitive inhibitor bind on the enzyme, and where doe allosteric inhibitors bind?

Should be in homework. Why not just write down the Lambert-Beer law and start plug in the numbers. Or ask if there is confusion to what is what.

Yus. Why a slap in the face when you can have electrocution collars?

Good points.

The text is very vague. I doubt that transport mechanisms are meant, as on the biological side it is more a conformational change more than anything else. Viruses do have exporters, to introduce genetic material into host cells, for instance. More classically it may refer to motor proteins of any kind (actin-mysosin for example). But again, the text except is rather too imprecise for my taste. Maybe passages before that hint at what they may be actually talking about.

All cells require potential across the membrane. But not an action potential. Membrane potentials are also involved in energy generation, however this is done across the mitochondrial membrane (or the cell membrane in case of prokaryotes.

Ionic interaction in the broadest sense. pH changes lead to protonation or deprotonation of reactive groups. These can change the the interaction of the amino acids within the proteins and hence the overall structure. It does not necessarily need to denaturation (i.e. loss of secondary and tertiary structure), but it may lead to a conformation that is less active than the optimal one. In other words, the optimal pH of an enzyme is when the charge load of the protein results in the stabilization of the structure with the optimal activity.

Geez, this is a long thread. I really do not have the time to read through all of this but it appears to me that its intended to be an early form of a research proposal. In this case it has to be scrutinized more carefully than a regular hypothesis that one just throws in as one of the function of a proposal is to demonstrate the relevance of the work to be conducted. As such, strong background information (aka preliminary results and literature data) that support the central hypotheses of the proposal are essential. Of course, it cannot be expected that posts on a forum will equal a research proposal of any level. Nonetheless if let students write a short proposal of any kind, I expect roughly the following elements: Background: what is the problem/question to be answered, to what is it related and what is new about it? Which knowledge gap is there? Central hypothesis: what is the proposal based on? What is the rationale behind it and what supports the hypothesis? Specific aims: How do they relate to the central hypothesis and how do they answer the proposed questions. There have been a lot of comments already and as mentioned, I have not read them all. But based on the initial post there is little evidence that supports the assumption (or central hypothesis) that perception preference correlates with certain facial features. As noted, proposals need a basis and this is not provided sufficiently in the post. The remainder of the post deals with specific without establishing the basis first. In other words, you would first have to find good reasons for your central point before more detailed analysis would begin to make sense. In other words, unless you find literature data, you would have to design an experiment that would demonstrate that there is a strong correlation with perception type and facial features. This requires a very strong design that would account for any number of confounding factors, utilizes the right statistics etc. The problem is that in the remainder of the post you already jump to possible mechanisms without establishing the basis first. Research generally takes small steps to succeed.

Where is Azure? I heard she is good with macaques.

It was near to impossible to find anything recent in journals. The latest positive one regarding primal therapy was from the eighties with a ridiculous low N (around a dozen or so). The newest one is from 1996 is less positive The abstract (My bold) Starker and Pankratz Psychol Rep. 1996 Feb;78(1):288-90. Quite apparently it is far from being an accepted basic technique.

Actually potential carcinogens are all substances that have some amount of mutagenic properties. An actual link to cancer does not need to be shown, nor is it likely to be found unless someone gets contaminated with something in extreme amounts. Cancer preventing is mostly a non-scientific term. It is used by nutritionist (and about everyone else) either based on a association studies that found that populations with a certain diet have lower incidents of certain types of cancer (those there may be confounders and usually there are few if any proposed mechanisms). There is to my knowledge nothing that is truly cancer preventing inasmuch as it has a real mechanistic effect. Especially given the fact that the precise mechanisms of cancer cells is not understood either.

The question is do you need a biosafety cabinet, a clean bench, or a fume hood? Bioafety cabinets are mainly for the protection of the user (laminar vertical flow). They also give a degree of cleanliness (due to HEPA filters) but user protection is the primary function. Fume hoods are an even better protection as it actively sucks in air from the front, away from the user, but they introduce more dirt into it. And finally there are clean benches. The do not protect the user at all, in fact all the stuff gets blown into your face, but due to a clean horizontal flow your sample gets better protection from contamination. Some of the fancier cabinets have a combined vertical and horizontal flow, though. However, neither biosafety cabinet nor clean bench are suitable as a fume hood substitute. Though with certain exception there is no good reason to use a fume hood for bacterial cultivation. It is quite complicated to keep things sterile there. But yeah, if your concern is sterility a clean sterilized glovebox would be a cheap alternative. Also it depends a bit on your bacteria. Fast growing buggers like E. coli and similar that are BSL1 can also be easily cultivated on a clean benchtop while using sterile techniques. Working near a Bunsen burner also helps. The latter is especially important if there is a risk that your lab has spores of some kind around.

Well, yeah. Cancer is just a radical manifestation. One question is what you mean by expression. Mutations in non-coding areas are also an option. In fact, cancer can also be associated to mutations in regulatory (as opposed to coding) regions. Both are in principle detectable (e.g. by highly parallelized hybridizations or direct sequencing) though take quite time and effort.

Or moved into a given gene pool by horizontal gene transfer.

Fast responses are not our strength. It is odd, however, that anyone should explain IEF without explaining isolectric points (pI). There are a number of ways to do that (with varying accuracy) according to the pK of the amino acids. And right there is the hint you need. Second hint, the pI is the point where the net charge is zero. That being said, just by looking at the peptides I find it unlikely that that one of the peptides is actually in the high basic range. Check up on the properties of the listed amino acids and you will see what I mean. If you are interested in following that up, read Bjellqvist, B.,Hughes, G.J., Pasquali, Ch., Paquet, N., Ravier, F., Sanchez, J.-Ch., Frutiger, S. & Hochstrasser, D.F. The focusing positions of polypeptides in immobilized pH gradients can be predicted from their amino acid sequences. Electrophoresis 1993, 14, 1023-1031. Edit: I misunderstood the post. I assumed that you did not had heard about pI, but apparently you had it for AAs already. In any case the precise determination for whole proteins is a bit trickier. However, knowing the pI of the AAs will give you a good hint what to expect from the short peptides. One problem is, however, that the presented peptides are so short that most predictions will be off.