Gabriel+S.

=The Effects of Caffeine=

June 1, 2014
Caffeine is a great way to help people get through the day, and if taken in moderation can be virtually harmless to an individual, on top of many positive effects. That being said, caffeine is definitely no stranger to negative side effects. It affects our state of mind, making us feel more alert and awake than before, which is why people often consume coffee in the morning to wake themselves up.

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Here is a brief video touching on how caffeine works within our bodies, among other topics.

Caffeine is a common stimulant, which many people intake daily. 83% of all adult americans drink coffee, but it is unlikely that that many are aware of what exactly caffeine does to the body. Unless taken in huge quantities, the effects of caffeine aren't too bad. To understand how caffeine works, one must know what adenosine is. Adenosine is an inhibitory neurotransmitter. Essentially, throughout everything we do, we have neurons firing off all day. With every instance of a neuron firing, adenosine is produced. As the day goes on, more and more adenosine accumulates within you. Your body is constantly monitoring your adenosine levels with receptors. As the adenosine accumulates, your body begins to want to rest more and more. The common consensus on caffeine is that it makes you more awake and energetic, which is only true to a certain extent. Caffeine and adenosine have a relatively similar chemical structure. So, when caffeine enters your body, your adenosine receptors believe it to be adenosine. From here, the caffeine actually bins to the receptors, and clogs them up. At this point, the brain's natural stimulants, dopamine and glutamine can do their job more freely, and work with greater effect.

Caffeine is a very common and popular substance found in many popular drinks and foods in Canada. It should come as no surprise that some products, such as tea or coffee, have caffeine in them. Others may be somewhat more surprising to hear that they have it in them, such as chocolate, ice cream and even weight-loss and pain-relieving pills. For the average adult, most doctors recommend keeping the body's caffeine intake below 400 mg per day, although this will vary from person to person. To put that into context, a large Tim Horton's coffee has 200 mg of caffeine, so you would be fine to drink two of those per day. A can of Monster energy drink (which is 500 ml) has around 160 mg of it, which honestly isn't terrible. Although, it becomes an issue when people (teenagers) drink several of these back-to-back, especially if their body isn't too developed and can't handle caffeine as well as others.

Further Reading:
For more information on the caffeine content of popular drinks, please visit: http://www.caffeineinformer.com/

For more information on products which are surprising sources of caffeine, please visit: http://www.health.com/health/gallery/0,,20313656_2,00.html

For more information on the effects of too much caffeine, please visit: http://coffeetea.about.com/od/caffeinehealth/a/Excess-Caffeine-Symptoms.htm

For more information on how caffeince actually affects your brain, please visit: http://lifehacker.com/5585217/what-caffeine-actually-does-to-your-brain

Sources Cited:
http://lifehacker.com/5585217/what-caffeine-actually-does-to-your-brain http://www.foodmanufacturing.com/news/2013/04/consumer-trends-83-percent-americans-drink-coffee http://healthycanadians.gc.ca/recall-alert-rappel-avis/hc-sc/2013/34021a-eng.php http://www.caffeineinformer.com/ http://www.personal.psu.edu/afr3/blogs/SIOW/2011/10/why-does-caffeine-wake-us-up.html http://www.health.com/health/gallery/0,,20313656_2,00.html http://www.hc-sc.gc.ca/fn-an/securit/addit/caf/food-caf-aliments-eng.php https://www.youtube.com/watch?v=Xl1XBJLfIDU http://coffeetea.about.com/od/caffeinehealth/a/Excess-Caffeine-Symptoms.htm

=The Evolution of Snakes=

May 2, 2014
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Overall, snakes may come off as weird, disgusting and somewhat unsettling creatures, but they still represent a very interesting evolutionary development which w e are still uncertain about to this day. Given their undeniable resemblance, it shouldn't come off as much of a surprise that it is thought that snakes are descendants of lizards. The glaring difference between the two is that snakes lack the arms and legs which lizards have. The evidence we have which supports this route of evolution is that ancient snake fossils suggest that snakes used to have those limbs, but over thousands and thousands of years lost them. Pictured below is a 95-million year old fossil found in Lebanon which is believed to be an ancient snake with preserved leg bones. =====



One common question is why did the snakes lose their limbs? Lead author of Journal of Vertebrate Paleontology, Alexandra Houssaye explains it well in saying "If something is not useful it can regress without any impact on the (animal's) survival, or regression can even be positive, as for here if the leg was disturbing a kind of locomotion, like for burrowing snakes or swimming snakes,". It is thought that the snake must have evolved from a lizard which primarily burrowed on land or swam in the ocean. Apparently, having limbs must have proved to not be very useful for that plan.

Above is 95-million year old fossil found in Lebanon with preserved leg bones, believed to be an ancestor to the modern snake. All and all, there is actually quite a bit we do not know or understand about how snakes came to be. This is probably because, often times, snakes are rather small and fragile. In turn, this leaves us in a place where ancient snake remains are even harder to come by because of the fact that they are much more likely to be destroyed in nature than other fossils. That bein g said, one of the oldest snake fossils ever documented is 90 million years old and was found in 2003 in north Patagonia, Argentina. Pictured here below on the right, it shows one very interesting characteristic. Not only does it have legs, but it also has hips.

To the left is a cladogram which shows relationships among snake lineages, starting at madtsoiids (which are a very primitive extinct group of snakes which date back around 100 million years old).



Is it commonly believed that snakes and lizards share common ancestors and that snakes are the descendants of lizards. Although, there does exist another possibility which is worth looking into. It is thought that Snake ancestors may very well be aquatic. Specifically, they have been been hypothesized to have descended from a marine reptile known as the mosaurus, which dates back to 100 millions years ago. That being said, the discovery of the fossil pictured on the right does show critical evidence pointing towards snakes evolving from lizards. For starters, the fossil itself has a well-defined sacrum which supports a pelvis as well as functional hind legs out of the rib cage. Secondly, when compared to previous ancient snake fossils, this one shows a much closer connection to its four-legged ancestors. Lastly, this fossil was found in a terrestrial deposit, which highly suggests that the animal itself must have lived on land and not in an aquatic environment.

Above is a 90 million year old snake fossil which gave significant clues in regards to whether snakes originated from an aquatic or a lizard which lived on land. Below is a video which talks about another interesting dynamic of snake evolution, which is their venom.

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On a very related note, there is a theory which suggests that much of primate development is actually due to the presence of snakes. For instance, early mammals had to develop a way to avoid contact with snakes. They achieved this by developing a better eye for color and movement, so snakes could be more easily detected. Consequently, the snakes became more efficient predators by developing the capability to produce venom, making them much more lethal.

To the right is a picture demonstrating just exactly how most snakes inject their venom into their prey.

February 27, 2014


In 1931, a chemist by the name of Arthur Fox accidentally made a very intriguing discovery. While working with a chemical, some of that chemical sifted through the air. Fox's assistant complained about the bitter taste of the substance. This struck Fox with confusion, as he himself di d not taste anything. Fox went on to ask others to taste the chemical. Some complained about the taste, while others had a reaction like Fox's and tasted nothing. It was discovered in 2003 that the reason for the different perceptions of taste was centered around the ability to taste phenylthiocarbamide, which is also known as PTC. What is essentially all boils down to is the gene TAS2R38. The capability to taste PTC is best-linked with a more dominant allele of the gene. This whole experience dawns the question: what is the link between taste and genetics?

To the right is an image which explains the process by which humans perceive bitter taste.

media type="custom" key="25242028" Above is a brief video which explains the basics of the relationship between genes and the capability to taste bitterness. It also touches on how the research itself is done.

Human taste can be divided into five basic categories. Those categories are sweet, sour, bitter, salty and umami. The receptors of bitterness, sweetness and umami have all been identified as to bind to the g proteins. The genes TAS1R1 and TAS1R3 and embodied with proteins which affect how strong our preceptor of glutamate is. Glutamate is often interpreted as the umami taste. Similarily, the genes TAS1R2 and TAS1R3 encode our preceptors for sugar and sugar-like substances. It has been suggested that there is less difference in the perception of umami than there is in the perception of sweetness between different people. The evidence to back this is is that a study in 2006 showed less variation in the genes which perceive umami, when compared to those which perceive sweetness.

Umami is a rather different kind of taste when compared to the others, and is somewhat hard to describe. It is less noticeable than the others. It is characterized by a long-lasting savoury taste, which leaves a sort of odd sensation on the tongue. Is it said that ripe to matoes are bountiful in umami taste.



To the right is a diagram illustrating how different tastes are percieved by different parts of the tongue.

While there is definite ly a link between tasting and genetics, is it not fair to say that it is the only factor in determining preference of taste. Studies have shown that there is more often an genetic link when more nutrient-dense foods are being consumed. The opposite applies with foods which are starch, salty or dairy.

To the left is an image which gives an explanation in regards to how tasting capabilities may be passed down genetically between a set of parents who do not have the same tasting receptors.

Another factor which determines our preference in taste is age. I remember personally hating bananas as a child, but now I enjoy eating them. This is because, like with all senses, taste changes and develops with age. So ultimately, how we perceive taste is most definitely affected by our genetic make up, but that is ultimately not the only reason why we prefer some foods over others. What you prefer to eat is a matter of personal taste (what a distasteful pun).

Sources Cited
http://en.wikipedia.org/wiki/Umami#cite_note-Yamaguchi_Food_Rev_98-19

http://www.msginfo.com/about_taste_umami.asp

http://michaeldmann.net/mann10.html

http://www.topnews.in/health/chemical-blocks-peoples-ability-detect-bitter-aftertaste-discovered-27582

http://io9.com/are-there-some-vegetables-you-cant-stand-it-may-be-ge-1532668567

http://learn.genetics.utah.edu/content/inheritance/ptc/

http://www.ncbi.nlm.nih.gov/pubmed/16124860