Bacteria and Quorum-Sensing

Summary of Article


Bonnie Bassler and her lad work on quorum-sensing at Princeton.  They main focus is to figure out how bacterium communicate with one another. There are many types of bacteria, both good and bad, that are all over the place. So what does Bassler do? She works with her students to figure out how these good and bad bacteria communicate to fight against each other. Instead of using words, she believes that they sense things and react with one another.


What is Quorum-Sensing?


Quorum-sensing is just another way of saying bacteria work together, communicate, and function well in groups. Bassler works with these bacteria, which are single-celled organisms that have no nucleus and only one piece of DNA. These bacteria cells do reproduce, but not as we do. They reproduce asexually, meaning that they just get larger and make an exact replica of themselves and just simply divide in half. After they reproduce they release a chemicals that we call auto-inducers, but is more commonly known as hormones. It starts out with a little bit of this molecule but when you get more bacteria to reproduce, you get more auto-inducers. One way to demonstrate how they communicate is when there is a lot of bacteria and auto-inducers, some of the bacteria start clinging onto the molecule because there are a lot of other bacterium around and they think they need to change their behaviors. This all got started because of a glowing substance known as Vibrio harveyi. They had put some bacteria in with this but it didn't glow as much, but when they added more of this bacteria, the glow started to get brighter. This is showing how Quorum-sensing really works because the glow is being controlled by quorum-sensing.

Wallace Carother and Nylon

Wallace Carother was a fine chemist.  He first went to school to major in accounting but then changed his major to science.  He left his job, teaching accounting at Harvard, to take a new job as the head of the research team at DuPont, where they were trying to make new silk like materials.  During his experiments to make a synthetic silk, Wallace made the process better by adjusting the tools that they used.  This made better and stronger fibers.  After a long period of time, he finally came out successful. He had found the way to use polymers to make "nylon". 


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In Wallaces' work, there is a relationship between science and engineering.  In order for Wallace to reconstruct the tools and equipment that he used, he needed some kind of engineering. The definition of engineering is "technology: the practical application of science to commerce or industry" according to the google.

The invention of nylon was revolutionary because it was during the time period of WW1.  This was when we were at war with Japan, who had supplied the U.S. with silk, so our trade was breaking apart.  But with this new synthetic material, we are able to by durable clothes for less. With nylon we are able to manufacture more and people will buy more because it is cheaper than buying actual silk.

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Everyday, everyone comes in contact with synthetic materials.  I come in contact with many types of synthetic materials, such as paper, clothing, and anything that might be made of rubber. What if synthetic materials never existed?  We would be wearing leather and silk, which would be a lot more than buying synthetic materials.

STEM CELLS: BIG STEP FOR A CONTROVERSIAL SCIENCE

It was said by Korean scientist, Woo Suk Hwang, that  his team had finally derived stem-cell lines from cloned human embryos.  These new lines were taken from patients skin cells with spinal-cord injuries.  Using "therapeutic cloning", skin cells merged with eggs whose nuclei had been removed.  This caused the new stem cells to be genetic matches for the patients.  It is believed that this will replace unhealthy tissue without "fear of rejection".  In some states in the United States, this procedure as been banned because they believe it could lead to human cloning.  Doug Melton was actually given permission to further his studies so he could help create stem cells for people with Parkinson's, Alzheimer's and type 1 diabetes. 

I started out thinking that this was a bad idea.  In my own opinion it wrong to clone people.  Then after reading on, I figured out that they are starting to clone stem cells to help cure people with Parkinson's, Alzheimer's, and type 1 diabetes.  My grandfather has diabetes and it is always nice knowing that someone will find a cure for something.  Even though I thought cloning was bad, it still has it reasons for helping others in the future.  It may even help me!

For a Rare Few, Driving and Cell Phones Go Well Together

Yes! Researchers are finding that some people can multitask, meaning and text and drive.  But the catch is, they can multitask well.  Researchers call them "supertaskers".  It was proven that one in 40 drivers can multitask and do it well.  These "supertaskers" are able to do more than two things at once and still maintain a safe distance between them and the car in front of them and also hit the brake with the right amount of force while still maintaining that distance.  During the tests, they would have these drivers sit in a driving simulator on a virtual highway, so it was like playing a video game.  While these college students were driving, researchers would send them math problems and they would have to solve it while still paying attention.  Out of 200 volunteers, only five were considered "supertaskers". 

I enjoy texting and driving, but not at the same time.  This is a very interesting article but it is also giving people and young adults the wrong idea.  Especially because not everyone can be a "supertasker".  I don't think it is safe at all to text and drive even if your are considered a "supertasker".  Talking and texting on the my cell phone is one of my many hobbies, but I would never put my life and even the lives of others at risk by trying to be a "supertasker".

DNA-damaging disinfection by-products found in pool water

A  study  found  that  the  chemicals  used  in  pool cleaners, can damage your DNA cells.   The disinfectants, such as chlorine and other cleaning supplies, form mutagenic chemicals.   Swimmers went through numerous tests before and after swimming for forty minutes.   They found that the micronuclei increased the number of white blood cells.   The micronuclei was said to have caused the chromosome to break.   Trihalomethanes most likely entered the body through respiration.   It was also tested that the pool water was too toxic.   Scientist believe that most of these by-products are due to reactions with the cleaning supplies and swimmers urine, sweat, and skin.   They were able to find some cleaning supplies to make the pool water no more mutagenic than drinking water.

A lot of people like to swim, especially in the summer.   If people are getting sick because of the pool water being so toxic, most people aren't going to swim that often. I personally love to swim, that is why i chose this article.  I want to know the facts so i am able to protect my health.  Some ways we can prevent our DNA cells from damaging is by not urinating in the pool or sweating while you are swimming.  It is hard to keep yourself from sweating while in the pool so we can do our best by simply not urinating while in the pool.  To fix this problem simply go to the bathroom before you get in the pool and at any other time while you are in the pool.