41

Just Chat! / Re: Nice work on the Olympics!

« on: 31/07/2012 23:25:46 »

Organisers of the Olympics have criticised those selling their torches’ for making a profit out of the Olympics. Strange, I have seen no such criticism of the corporate giants like Coca Cola, McDonalds, Visa, Omega and BMW doing exactly the same.

Would these be the corporate giants who've made the event possible by making up more than 90% of the total funding?

I thought the first 9,097 hours (that’s how long it seemed to me) was a tedious depiction of life in Britain during the Industrial Revolution. A bunch of seemingly unchoreographed plebs, meandering about doing little or nothing. Not exactly the height of excitement, let alone an image of Great Britain being the sort of ‘great’ you would want to advertise. A time of great inequality between the upper classes and the working classes. Poor standards of education, if any, for the working class children, poor or unaffordable healthcare, poor housing, poor nutrition, great child mortality, no job security, long working hours, low wages, poor and even positively dangerous working conditions, austerity, Rickets, TB etc etc etc.

Like it or not, that is our history. You can either sit there and be ashamed of it, or you could actually acknowledge that the Industrial Revolution was arguably the greatest force of social change that has emerged in the history of humanity. That started here. That is what we've given the world. Personally, I feel rather proud of it and I'm sick of people apologising for it on my behalf.

The Dambusters March??? Oh! Very good, that wont offend anyone will it??? A celebration of the RAF’s 617 squadron attack on the dams of the Ruhr Valley during WWII. That should please the German contingent. Why not get a Lancaster Bomber flanked by a Hurricane and a Spitfire to do a fly-past and have a neon sign displaying the legend ‘We won the war’!

Again, that is our heritage. And also again, I'm sick of people apologising on my behalf. This isn't about appeasing Germany. It happened. An awful lot of people consider the actions of our brave troops in the world wars to be an integral part of our history, and underline what it means to be British. It shouldn't be ignored or brushed aside, or anything else. It is a part of who we are, whether you like it or not.

Twenty – seven – million – pounds! Twenty – seven – million pounds!!!

£27million pounds, for an advert that reached more than 1billion people across the globe live. Not to mention the millions more who went on to read about it in the foreign press -- it has been celebrated in the American media like the NYTimes; in Australia; in the Times of India; in China; across the entire globe. You may sniff now, but London's laughing all the way to the bank. That advert has made London the place to be, and it's an advert that's going to attract people to London for years to come, never mind the country as a whole. In the short term, yeah, sure, whatever, tourists are down. In 2-3 years time? The returns from the advertising will more than make up for £27million.

Ta.

42

Plant Sciences, Zoology & Evolution / Re: Which came first, life or DNA?

« on: 31/07/2012 13:34:30 »

I realise that they're perfectly capable of existing before life appeared, but I suspect they would have been a later addition to life (or what 'life' then was). They're not the imperative components to get life going, that's what I meant by them being a later addition.

43

Chemistry / Re: Is there a safe glow-in-the-dark liquid?

« on: 27/07/2012 12:48:02 »

For glow in the dark purposes there are biochemical options. Luciferin + luciferase reactions produce light, as seen in fireflies. There are also fluorescent proteins, such as GFP and Aequorin, that can be recombinantly popped into bacteria. The amount of light wouldn't be great, but might be handy in highlighting steps or something in the dark.

44

Plant Sciences, Zoology & Evolution / Re: Which came first, life or DNA?

« on: 27/07/2012 12:16:40 »

DNA length varies enormously between different organisms. This is usually referred to in terms of base pairs (bp) or Kilo-base pairs (Kbp). According to Mr Wikipedia, the (haploid) human genome is believed to be about 3.2billion base pairs long, so in a standard cell, excepting sperm or eggs, you will have 6.4billion base pairs of DNA as one set of DNA is inherited from your mother and the other from your father. This supposedly contains somewhere around 20,000 distinct genes, but this DNA will also contain large amounts of 'junk' (that may yet be found to play some role) and repeats and all sorts. To contrast, E.coli has about 4.6million base pairs. Having said all that though, the amount of DNA doesn't necessarily reflect the complexity, or lack thereof, of the organism.

DNA contains 4 different bases, GATC, and every 3 base pairs is referred to as a codon. Each codon codes for an amino acid (some amino acids are coded for by more than one codon). As you have 4 different bases, and there are 3 pairs per codon, you have 4*4*4 = 64 possible codons which between them code for the 20 different naturally-occurring amino acids. The codons come together as genes to produce amino acids in various sequences, such that particular proteins are produced. There's no real limit to the size of a protein, so in theory the length of DNA can affect variety in that it enables more codons and hence more genes to 'fit on'. But, in practise this is not the case because DNA can contain huge amounts of junk.

The origins of life are completely unknown, with some interesting hypotheses. I think the big steps towards life are the emergence of a system of replicating nucleic acids (be it RNA, DNA or some other NA), and the emergence of some kind of membrane to protect it all and enable it to happen. In all life-forms we know about, nucleic acids are fundamental as they enable the transfer of genetic information from one generation to the next. Without this, the whole basis of life doesn't exist. For that reason, I think it's extremely unlikely that nucleic acids have emerged after life. Amino acids I suspect would have been a later addition. Nucleic acids aren't actually composed of them. DNA is made up of a deoxyribose sugar, some phosphate groups, and then either the G,A,T or C base. The DNA is a way of encoding the sequence information for all the necessary proteins in an organism in a readable and manageable form.

Apologies for the length of the post, but I hope it helps.

45

Physiology & Medicine / Re: Is a salty drink good in some situations?

« on: 27/07/2012 11:35:08 »

The primary method of treating cholera, which triggers diarrhoea and can lead to severe dehydration, is Oral Rehydration Therapy. This is basically salt/sugar water, with the salt and sugar at a certain ratio to best counter-act the causes of the diarrhoea. Diarrhoea is caused by an electrolyte imbalance, and particularly chloride, potassium and sodium ions moving out into the lumen of your gut. This in turn causes water to move out of the cells lining the gut, and into the lumen itself, by osmosis. This leads to the *obvious effects*.

By taking the salt/sugar water as part of oral rehydration therapy you help rectify this electrolyte imbalance, by supplying the cells lining the gut with more sodium and chloride ions. This then stops water being drawn out of the cells and prevents diarrhoea.

46

Physiology & Medicine / Re: Can an illness target a single species or organism?

« on: 27/07/2012 11:12:36 »

This is absolutely possible. Bacteriophages (literally "bacteria eating") are often highly specific in which bacteria they infect. Some, such as T4 and bacteriophage lambda, are specific to E.coli. This is a feature which has made them very useful in molecular biology and biotechnology.
There are many others too, that are specific to different species, and they'll possess adaptations to make them particularly efficient in catching their bacterial prey.

There are viruses that are specific to humans, such as HIV, but they are often closely related to other viruses that attack other species. HIV bears close similarity to SIV in other primates, particularly SIV in chimpanzees and Sooty Mangabeys.

47

That CAN'T be true! / Re: Is there a gene for liking marmite?

« on: 17/07/2012 15:17:59 »

Whether or not you like something surely must depend on how it tastes to you. Since the genetic makeup of an individual may make them more or less sensitive to a particular compound in some foodstuff (i.e. affects how it tastes to that individual), then surely isn't that at least contributing to whether or not they like it?

To what degree genes determine taste I am uncertain. It is known that the ability to smell plays a huge role in taste, and I seem to think I was reading somewhere recently about a lady who lost her sense of smell, and with it her ability to taste food. The sense of smell involves chemo-receptors in the nose, and genetics could potentially play a huge role in taste on this basis.

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That CAN'T be true! / Re: Is there a gene for liking marmite?

« on: 16/07/2012 17:31:53 »

It is entirely possible. Here is quite an interesting chemical that exhibits an interesting property:  http://en.wikipedia.org/wiki/Phenylthiocarbamide (apologies for the ugly link). Some people don't notice this, whilst other people can become almost sick because of the taste.

Off-hand, I don't know if there's a gene for liking marmite. But, bearing this chemical in mind, and knowing that genetics is involved in being able to taste it, then I really don't see why not.

49

General Science / Re: What is the meaning of life to a scientist?

« on: 16/07/2012 17:19:49 »

The meaning of life, to my mind, is what you make it to be. In essence, it's meaningless -- what is the meaning of anything? Life is a product of a set of particular conditions within the Universe at this point in time. The 'point' of life, if you like, is simply to pass genes on to the next generation. From this and by evolution by natural selection, we have the range of organisms we have today. Somewhere along the way consciousness has emerged, which has enabled us to perceive the world around us.

We try to give it meaning, when essentially there is none. Many people try to get around this by giving it a meaning, possibly via religion or some other means. That is completely up to the individual, and if that makes them feel better then that's fine.