jimmydasaint

As a teacher I am somewhat puzzled by the choice of a person to become either an 'outcast' in a class or a person that becomes the target of bullies. I have tried to find something that is different about the bullied but cannot see it. For example, I taught a girl that was bullied by the rest of the class. The class would make comments about her, for example: 'she smells'. However, she was clean. The members of the class that indulged in the bullying were a cross-section from 'good' to 'naughty' students. In another case, a boy was tortured daily by others in the class verbally. I could not see any difference between him and the others. It was not racist because other members of the same race were participating in the abuse. A speculation could be the type of response to an insult by a pupil. If the response is not measured and extreme from a bullied child, it becomes a source of constant amusement to 'press the correct buttons'. The more extreme the reaction, the more sustained the bullying. Curiously, though, the very bright are exempt from the bullying regardless of individual eccentricities because the 'lads' and 'ladettes' actually wish they were as bright and respect brains. Any other speculations though on the choice of the bullied by the bully? [i should mention that I am appalled by bullying and do everything I can to help the bullied]

Thanks for the correction. I should have sussed this out. However, the controversy of the OP is about the presence of T in tRNA hence he/she regards this as controversial. So far, he/she has not recived an answer.

I don't know about ESS but I assume it is too simplistic to assume that mutation, selection and reproduction in Natural Selection provides a complete description of an organism's interaction with its environment and the inheritance of subsequent traits. (I would also add in facilitated differentiation as a sub-note to phenotypic plasticity). I quote: http://lib.bioinfo.pl/pmid:17924956

Thymine is in DNA. DNA has four bases: Adenine (A), Thymine (T), Guanine (G) and Cytosine ©. DNA has two strands with these four bases bonded to each other and able to make long sequences millions of bases long in and arranged in a number of chromosomes. Sites on the DNA which are more 'open' for the start of making messenger RNA (called transcription) tend to have runs of Adenine and Thymine because there are only two hydrogen bonds between A and T. G and C on opposite strands have three hydrogen bonds. RNA is found in three forms - tRNA, rRNA and mRNA. The Adenines are bonded to Uracil (U) a different base from thymine. IMHO the uracil can be recognised by enzymes that bind to RNA. Is that what you meant?

YT - great stuff. Why did the green trees not look green when the green filter was held in front of them? Just a simple question which probably has a simple answer.

I hate to be a spoiler of this good atmosphere but I don't know if we can extrapolate from yeast to man in that way even if genes are conserved there are whole modules of gene control which are not taken into account for a motile organism which is independent of its environment- I would still stick to decaffinated mocha latte

Try smallpox or other viruses from bodies defrosted from tundra http://www.livescience.com/environment/080327-smallpox-corpses.html or bacteria being released from defrosting and 'reawakened' after millenia or even, theoretically, millions of years. http://www.msnbc.msn.com/id/7019473

This is a simple minded explanation (typical for me) but I regarded epigenetics as the study of the way that certain genes are switched on and off in response to environmental conditions, for example, starvation, in a way that is inherited by future generations. However, in any single organism, the chromatin must be packaged in a way that certain genes are 'on' or 'off' by mechanisms mentioned in the previous posts, so that epithelial cells (epi=outside; thelial = layer) will always be replaced by other epithelial cells when damaged or killed. IMHO, the organisation of chromatin is central to all differentiation anyway, which is the process in which cells containing identical genes become different - some becoming muscle and others becoming skin etc... however, in cases of starvation, it seems that the 'on' and 'off' pattern of genes is inherited by at least a generation after the original starving generation. This, I think gives the name to epigenetics.

I take it you want to examine immune response in terms of blood and lymph antibodies and then examine celllular responses from cell 'munchers' e.g. macrophages. There is a really simple system for measuring the antibody responses to the molecules that cause an immune response called antigens. This is called radioimunoprecipitation. Firstly, choose a particularly obvious marker from tumour cells. Next, radio-label it using easily purchased reagents (e.g. Bolton hunter reagent to label lysine amino acids on proteins or protein-containing antigens). Next perform an antibody extraction using serum from the affected animals. concentrate it if necessary and then add whole serum to the radiolabelled antigen (cell surface marker). After incubation, separate antibodies from captured antigens using SDS or mercaptoethanol and run an SDS-PAGE gel of all the antigens identified. Use a lane of the gel for common molecular weight markers and also include a negative control and a pre-treatment control. Any extra antibody response can be picked up quite nicely. If you want to examine non-cellular responses, this is a bit more complicated. tell me if this advice makes any sense because I suspect you may be looking at purely non-specific responses.

Wonderful! I will use these in my teaching. Kids love the sheer excitement of Chemistry. Well done mate. Funny and informative. Now, if only teaching was like that!

On a side note, here, there are also some beautiful images of gold atoms reconstructed from a scanning tunnelling electron microscope. So atomic surfaces that are smooth enough can be 'seen.' Here's the image:

Very interesting. However, would it be possible for an asteroid to slip by unexpectedly which is unaccountable in terms of predictable elliptical orbits? For example are we as a Solar System not moving round as well? I just wonder what would happen if our Solar System rotated into an area of the Milky Way that is heavily populated by asteroids? Or are these factors taken into account by NASA?

In reality, there is not a lot of hope is there? I take it that you cannot nuke an asteroid which is above 1km diameter to avoid contamination of the Eart's atmosphere. I just wonder if it is possible to nudge it away somehow. However, how much time would be required to organise such a life-saving mission - 24hrs, 48 hrs, a week. For example if you could take a spaceship up to land or to fire a solar sail on the asteroid, it could be nudged away right?

This is a question that puzzles me. I take it that Near Earth Objects such as Comets or Asteroids that are on a trajectory that will hit the Earth can be detected well in advance of hitting us. However, does the technology yet exist to deflect a dangerous asteroid? For example, if an asteroid was over 1km in diameter, do we have any chance for survival? Views and opinions welcome.

Apart from showing duality of matter, what other interest would there be in sending buckyballs through the slits?

My knowledge of Physics does not extend far beyond K10 or the UK GCSE. However, I read that buckyballs (C60 =bucminsterfullerene) forced into diffraction slits caused an interference pattern typical of waves, demonstrating, once again, the duality of matter. http://www.quantum.univie.ac.at/research/matterwave/c60/index.html#Motivation If this is the case, and we become Spike Milligan silly here, can you fire a series of cats through an appropriate slit diameter and get the same pattern?

Thank you for the compliment. I love the thought of crocodiles being so muuch superior to humans. IMHO the crocodile blood extract will be purified and used as an effective antibiotic. HIV is a different ball game because it can swap portions of its genome with other HIV's and come up quickly with a new 'strain' which is resistant to the antiviral.

Thanks for the clarification about population size. However, the next part is counter-intuitive to me - the model does not work anywhere in the real world yet it is still useful. So the model is actually not useful in a real world scenario except at predicting stable inheritance of recessive genotypes. There must be better models surely?

With respect, doesn't the Hardy Weinberg Law make some strong assumptions? For example small population size, negligible rates of mutation, no natural selection taking place, random mating, no immmigration or emigration from the population,,,(this is from memory so I hope this is right)

Excellent questions. In regard to blood transfusion, I think that the components are processed after collecting the blood so that red blood cells, platelets and plasma are separated. Moreover, leukoreduction can reduce the number of white blood cells in the blood. So I think that you can minimise the chance of rejection responses from the recipient of the blood. http://library.med.utah.edu/WebPath/TUTORIAL/BLDBANK/BBPROC.html Moreover, care is taken to match for as many antigens as possible. IMHO, the biggest problem is in preventing infections from the blood donor to the blood recipient - HIV cross infection has been a good example of this problem.

I think this Forum allows teaching and learning so let's learn together. This site shows pictures of the filament fusion that ocurs during Spirogyra mating. Isogamy seems to indicate that the sixe and appearance of the gametes is pretty much identical right? And that isogamy involves a significant size difference between gametes (like human sperm and egg). Well, take a look at the pictures and see what you think. http://www.micrographia.com/specbiol/alg/filamen/fila0100.htm In fact here is a picture and judge for yourself which one it is: Of course I meant anisogamy for sperm and egg

This is not news but I would love for someone to update it. Apparently blood from crocdilians is highly effective, as an antibiotic, against fighting bacteria. It also seems pretty effective at fighting HIV (which antibiotics cannot destroy). In fact crocodile blood extract may be excellent at treating MRSA(methicillin resistant Staphylcoccus aureus) which have annoying resistance to a number of different antibiotics in hospitals. http://www.planetark.com/dailynewsstory.cfm/newsid/32069/newsDate/17-Aug-2005/story.htm http://www.boingboing.net/2008/04/16/alligator-blood-anti.html

We are making some serious assumptions here about technology and that we will still be around to harness solar energy and deuterium energy. Heck, even right now the West is staring down Iran so that we can monopolise its oil reserves. Although China have the Shanghai Cooperation Organisation as a source of energy at present, eventually it will move from using coal to oil and when that happens.... conflict. IMHO we have roughly 50-100 years to develop alternative technologies to harness energy but most of the renewable sources are too dilute to support the current lifestyle of the West. Just an opinion...