CharonY

I second that.

Actually you would benefit most from lectures, if you read beforehand and only use the info in the lecture to fill up anything you did not understand. It is hard to concentrate throughout the whole lecture, write up everything relevant and at the same time invest enough brainpower to not only memorize but understand what is being said.

And that it is not transmissible by fish.

This does not invalidate medicine as one of the adaptive mechanisms per se. For one Darwin himself did not reject the possibility of Lamarckian inheritance (that came later with neo-darwinism and then modern synthesis), but even so it would at best be a historical distinction. Now one could argue that the modern synthesis assumes a genetic basis for evolution, however, as others already mentioned, the ability to relay information across generations does ultimately has a genetic basis. Medicine would only be a sub-part of it.

Heh, I could think of half a dozen ones. Though the question is do you want to know whether it can survive oxygen, or whether it requires oxygen?

It depends what is recognized as the epitope. Even then it depends on the amount of conformational changes upon binding to it. If you want to make a very precise quantitation, one should use (monoklonal) antibodies directed against an epitope not undergoing conformational changes upon ligand binding, of course. If your goal is just to see whether there is am up-regulation, it may mot be an issue, as with more receptors you would also see more signal. There might be a competition with the ligands, however, so this would only be a qualitative analysis. But again, it really depends where the epitope is. If it is not in the pocket it should work reasonably well (depending on the precision you require).

I think I should start breeding super flesh eating flies then. Anyone who is going to whack zombies with melee weapons: you are aware how bloody tiring swinging such a thing is? For the (very) untrained like me mere 10 minutes (or less) of kendo is sufficient let one drown in ones own sweat. And that is one-on-one and not one-on-horde.

Congrats, oldster

Maybe it correlates (negatively) with the intelligence of the woman? I recall a study in which it was found that females might find more masucline faces more (sexually) attractive, but slightly femalized faces were considered more trustworthy and were more desirable as partners. This does not really translate into bad vs nice boys, though.

Well there are other modes of horizontal gene transfer, including transduction via phages or natural transformation (though Eschericia and Enterococcusspecies are unable to that).

Plants and in fact all cells react to a host of stimuli. Both external and internal. Only because they do not run around does not mean that they do not sense and react to stimuli.

This is an oversimplification. What is [math]\Delta[/math]H in this case?

Heh, it has been mentioned countless times now, that formal definitions of life do not exist. But regarding viruses, if one thinks of them as living organisms, so can be our individual genes. See, they also reproduce and proliferate, albeit with the help of other genes and their respective gene products, not unlike viruses. So is the complete unit "life" or already sub-parts? Again, this is a question that is not possible to answer easily, as there is not a simple property of life vs. non-life. Rather this distinction was historically done instinctively (bird alive, rock not alive) and then a definition was made from the bottom up. Mind you, there are a number of consensus definitions, but they are basically based on a priori distinction.

Deinococcus radiodurans is radiation resistant, but it does not generate energy. The names of the fungi are given in iNows post (as is the link to the publication itself). Not to rain onto the parade, however the study only shows that the fungi grew faster if irradiated. They still require all the other nutrients. How the works and whether it is really feeding on the radiation or a more obscure secondary effect, is still unknown. Regarding the bacteria, those mentioned in the OP do not (as already mentioned) directly utilize radiation, however there are bacteria that breathe metals, including uranium, instead of oxygen, for instance (a process termed dissimilatory metal reduction, btw). Well it sure isn't. At least not if you look at bacteria. They have a lot of different means of energy metabolism, of which the above mentioned metal reduction was likely one of the earliest forms of energy generation. In theory this energy could also be utilized for carbon fixation, though few bacteria nowadays actually do that (most likely as photosynthesis is more effective in that regard). However the first bacteria were strict anaerobes so the food chain in that time could not start with photosynthesis. Edit: kind of cross-posted with iNow

Simple and for the same reason plasmids are not considered alive. It does not have a metabolism. Truth is, however, that "alive "is not really a physical property itself, but rather a collection of properties. Simply put: there is no clear-cut demarcation between alive and not-alive. As with many biological aspects everything exists in continua (to put it simply).

Bloody hell. Missed it. Now there is a second that I will never see again. Oh wait, here is another one...

Well, apparently economists disagree. One aspect often uttered was that the New Deal enhanced unemployment by raging wages. But according to Krugman: And to my simple and rudimentary understanding this makes a lot of sense.

Usually it is not much of a problem. Generally speaking, if the phosphate concentration is in the range of roughly 10-100 µM it is not growth limiting anymore. For many cells very high P-concentrations can in fact be growth inhibiting. If phospate buffers are used in media, they tend to be in the in the lower mmol range to avoid this. So, even if phosphate is the sole buffer, usually the utilization by cells does not alter the its buffer capacity too much.

Maybe one should start off how antiobiotics (ABs) work. Most ABs inhibit protein synthesis or by binding at the ribsomes (the "proten factory" of the cell) but they can also effect specific enzymes. Given the fact that in these cases the function of the ABs requires effective binding to their targets, a possibility of resistance is to have a mutation that alters this binding sites, so that the AB does not bind anymore. These mutation can occur randomly and once ABs are present there is a selective pressure to maintain these mutations (provided they do not inhibit the primary functions of the ribsomes/enzymes, of course). This kind of resistance is generally not transmissible. However, target proteins may be protected against ABs by certain modification by other enzymes, which in turn can be propagated across a population via horizontal gene transfer (of which plasmids are one means). Other means of resistance include: -prevention of the entry of ABs into the cell: many ABs are transported into the cell actively. The cell does not do it on purpose, of course, but the ABs may be co-transported by transporters. Modification of these transporters may enable the bacterium not to import ABs -inactivation of ABs by modification or cleavage -export of the ABs: some bacteria possess export system that effectively pump out ABs so that the intracellular concentration remains low. Now regarding the evolution of plasmids: this is a very interesting topic but I think it deserves a thread on its own.

Nope.

Maybe we should start off with giving an overview what biofuels are instead of throwing in specific opinions to various sub-subjects of it? Just a thought. AFAIK any fuel produced in relatively short term by organisms is considered biofuel. This is supposedly to contrast it from fossil fuels which are also the product of organism, but which took a long time to form. To my knowledge there are basically four main directions: -ethanol -hydrogen -biogas (methane) -biodiesel (methyl esters) I am no expert on any of these fields (though I do have close colleagues in the areas of biogas and biodiesel formation), so take my thoughts with a big chunk of salt. One of the main problems to date is that all processes depend on microorganisms and that at this time point the whole process is still too expensive. Moreover, no single approach is likely sufficient to cover the need of fuels we have got today. At least not with further developments. According to some calculations for example, more is lost than gained in terms of greenhouse gas reduction and fussil fuel dependency when land is switched to crop growth for ethanol production (see e.g. Hedegaard et al., Environ. Sci. Technol., 2008, 42 (21), pp 7992–7999). Biogas is also now already used, especially in agricultural settings, but usually the output is just enough to power essential elements on the farm itself. However, they are usually truly powered by waste (in contrast to ethanol fermentation). A disadvantage is that methanogenesis is a somewhat complicated process that requires more than one species of bacteria to run efficiently. As such its productions is more difficult to control. Biodiesel is interesting as the one can engineer the organism simply to produce the required lipids and it does not require the rather inefficient means of fermentation for biomass increase. An interesting approach was to use either cyanobacteria or algae, which can directly produce the lipids required for biodiesel synthesis without the need to given them costly carbon sources (except CO2, of course). Still, this is to this date too expensive, though I expect much from this approach, as one is not dependent on growing other biomass first for fuel production.

Weeeelll even if the world does not end.. what is a PhD good for anyways

The advantage is not only on the side of the bacterium, but that of the mobile genetic element itself, too. From the viewpoint of the plasmid its fitness increases, if it can be persistent in as many bacteria as possible. As such it exhibits mechanisms that allows conjugation. It is the similar to, say, viruses. In contrast to viruses, however, plasmids do not exhibit a protein structure that enables them to infect cells. So, if the plasmids would actually decrease fitness of the cells (as viruses usually do), they would vanish, as there would be selective pressure on the side of the bacterium not to take them up, and the plasmid has no way of forced entry. As such generally only plasmids with contribute positively to bacterial fitness (e.g. resistance, metabolic or virulence plasmids), persist within a population. In fact, mobile genetic elements (including viruses, transposons, plasmids etc.) are the purest example of egoistic genes. Either force the cells to to propagate you, or make it worthwhile for the cell to do so (and at the same time introduce means of propagating yourself).

^ That is why I like to have biologists around that are not of the molecular flavour.

At least in Germany I have not seen it used either. At least not in normal educational settings. Maybe in assessment centers...