Saturday, November 27, 2010

Compare and contrast genetic technology in agriculture (genetically modified (GM) foods) with the genetic technology for human health.

Genetic technology used for agriculture and genetic technology used for human health are both used to manipulate genes. For example, you can use both of them to determine which traits you want, and which traits you don't want. For both, it's not natural because you're pretty much changing their destiny. Also, with both anything can go wrong. The genes of a fruit you manipulate could have a bad strain of disease with it, and the person whose genes you manipulate could turn out missing a limb or a body part. In contrast, in genetic technology for agriculture if something goes wrong, it wouldn't be such of a big deal because the fruit could be eaten or thrown away, and that's the last you would see of it. But if you mess up on genetic technology used for human health then you could potentially put the persons life on the line, cause defects to the body, or endorse a potential harmful disease. In genetic technology for agriculture its possible to create better tasting crops, like fruits, and it allows for an increase of supply in a short period of time. The effects of this would be short lasting, and after a while everyone would forget about it. On the other hand, with human health, all you can do is pick out the desired traits for one baby, you couldn't make a whole supply. The effects of this would be long lasting, because the human being would have to live through their whole life carrying that trait, and no one would forget about it. Despite the good outcomes of genetic technology, it still serves as a potential dangerous threat with bad outcomes.

-By Kharishma Patel, Deepthy Varghese, Jeswina John, and Miranda Juergens  
8th period, Medical Microbiology, Rickard

Friday, November 26, 2010

Compare and contrast DNA and RNA.

DNA and RNA are molecules that hold the genetic information for each cell. Although both DNA and RNA are alike in many ways, they also have their differences. They are similar because they both have polymers of nucleotides. Both DNA and RNA contain sugars and base pairs. DNA is linked to a phosphate at one end and a nitrogen base at the other just like RNA. DNA and RNA are both found in the nucleus, but RNA can also be found in the cytoplasm. DNA and RNA are different because in RNA one of the nitrogen bases is switched out. Instead of having the base (T) Thymine, RNA has the base (U), which is also known as uracil. Even their shapes are different; DNA has a double helix while RNA is just one stranded. While DNA holds the genetic information, RNA is the copy of the DNA that is transferred from the nucleus to the ribosome for making proteins. The sugar present is also different. DNA is made of deoxyribose sugar, and RNA is made out of ribose sugar. DNA has the bases adenine, thymine, guanine, and cytosine, while RNA has the bases adenine, uracil, guanine and cytosine. While RNA has short chain of nucleotides, DNA has long chain of nucleotides. Despite their similarities and differences, DNA and RNA both play a very important role in determining genetic information.

-By Kharishma Patel, Deepthy Varghese, Jeswina John, and Miranda Juergens  
8th period, Medical Microbiology, Rickard

Thursday, November 18, 2010

Discuss the ethical dilemma of gene modification (designer babies). This post must include a minimum of 2 pros and 2 cons.

          Gene modification is the use of modern biotechnology techniques to change the genes of an organism. This is done by PGD, or Pre-implantation Genetic Diagnosis, in which doctors screen embryos before implanting them. Genes, which are made from DNA, are responsible for determining an organism's physical appearances, also known as phenotypes. Humans are often turning to gene modification which is also known as making "designer babies". Gene modification allows people, mainly couples, to be picky and choose specifically what genes they want for their child. Although gene modification might be ones first choice, it may not be the first choice for others. There are many positive and negative aspects of creating designer babies.

          One of the advantages is that gene modification allows people to design a baby specifically by their preferred standards. For example, if a mom wants her baby to have blue eyes instead of green eyes, or blonde hair instead of black hair, than she would easily be able to make that change. Another way gene modification be an advantage is because by looking at the genes, it is possible to determine if the baby will be born with any mutations or hereditary diseases. If this is caught at an earlier stage, then this would be prevented and the new life could live longer, and the family would be happy. It also gives the mother an advantage to choose traits that she considers good. If someone is going to have a baby it is most likely that they want their child to look the best, so therefore by picking preferable traits for the child she is giving birth to, she can stop worrying about how her baby will look like when it grows up.

          The negative side to gene modification on the other hand is that it isn’t natural. If you change a baby's physical appearance, then you are changing the physical appearance for the whole generation. The looks that are well known for in the family may not pass on. For example, if a family is known for having pretty brown eyes, and you "customize" your baby to having blue eyes, their kids will have blue eyes which would change up the family generation of having brown eyes. Genetic modification can also be a moral issue to some couples because in one's religion, questions could arise stating whether or not man has the right to manipulate and change the ways of God and nature itself. It could be believed that man cannot decide how a kid can look, and deciding so would be a violation to one's own morals. Another con is that if you already know how your baby is going to look, then it may not be much of a surprise. If genes are constantly crossing each other than it is possible that a whole new type of problem could arise, like a weird mutation, with an unknown solution. Even though you can prevent diseases, if couples are picking the most "popular" traits like blonde hair and blue eyes than most of the generation will end up looking alike. There wouldn't be anything that would distinguish ones phenotype from anothers. Also, if only the rich are able to customize their babies, than the poor may feel like they aren't beautiful enough and may develop low self-esteem. This could lead to a class system between the designer babies and the normal babies. Overall, gene modification has many advantages that could be very useful in human life, like preventing diseases, but you never know where it can lead you to. With gene modification, a whole generation might not have the certain flaws found in each person that makes a person beautiful and different from one another.

-By Kharishma Patel, Deepthy Varghese, Jeswina John, and Miranda Juergens  
8th period, Medical Microbiology, Rickard

Explain the connection of nitrogen base sequencing to unique DNA in organisms. You must include the nitrogen bases and their pairing.

DNA strands are composed of nucleotides which serve as building blocks of DNA and RNA. Each of these nucleotides contains a phosphate which is attached to a deoxyribose sugar, and one of the four bases which include: guanine, cytosine, adenine, and thymine. The base pairing is very important, because they can only pair a certain way. The nitrogen base guanine only pairs with cytosine, and the nitrogen base adenine only pairs with thymine. These base pairs are held together by hydrogen bonds. The nucleotides are arranged into a spiraled helix forming into what is known as DNA. It is very important for the nitrogen base structures to be paired correctly, because these nucleotides are what carry the genetic information in order to form a sequence of amino acids which leads to the creation of a protein strand. A single change in the nucleotide can cause a difference within DNA and can cause a change in the amino sequence of a protein. This is most commonly known as a mutation. A mutation is a failure to store genetic information correctly or faithfully. The way nitrogen bases are sequenced varies in different types of organisms. It turns out that different species of organisms have different proportions of bases in their DNA. This is what distinguishes each organism as different from each other. The only reason why humans aren't bananas is because humans have a different number of proportions in their bases than bananas or anything else. For example, one species might have DNA that has 30% Adenine, 20% Cytosine, 20% Guanine and 30% Thymine, while on the other hand a different species could have 20% Adenine, 30% cytosine, 30% guanine, and 20% thymine. Despite having different proportions all of the percentages of the bases equal to 100% and that is true for every organism. The nitrogen base sequence for a human is 30.9 % Adenine, 29. 4% Thymine, 19.9% Guanine, and 19.8% Cytosine. This sequencing is very important because if this wasn't the exact numbers as shown as above, then you wouldn't get a human, but instead you would get some other form of life. The smallest change in percentage can change the whole organism. For example, the base percentages of a chicken and grasshopper are almost similar, but they are still two different organisms. The base percentages for a chicken are 28.8% Adenine, 29.2% Thymine, 20.5% Guanine, and 21.5% Cytosine. The base percentages for a grasshopper are 29.9& Adenine, 29.3% Thymine, 20.5% Guanine, and 20.7% Cytosine. Even though these two organisms have almost similar percentages and the same amount of guanine, just those small changes in numbers distinguish what the organism will be. The proportions in the bases are what make a human a human rather than a bacteria or yeast. The proportions of yeast are 31.3% Adenine, 32.9% Thymine, 17.7% Guanine, and 17.1% Cytosine. If the nitrogen bases had these proportions in their bases than most likely you will end up with yeast, because these proportions are mainly for yeast, and only yeast. The proportions of E. coli are 24.7% Adenine, 23.6% Thymine, 26% Guanine, and 25.7% Cytosine. Because of these differences in proportions, it is impossible to be bacteria with the proportions of a human. The Nitrogen bases in the DNA play a very big role in determining species. Therefore it is necessary for the sequencing to be right, so yeast can be yeast, and human can be a human. 

-By Kharishma Patel, Deepthy Varghese, Jeswina John, and Miranda Juergens  
8th period, Medical Microbiology, Rickard