Albinism Essays (1256 words) - Skin Pigmentation, Albinism, Melanin

Albinism Essays (1256 words) - Skin Pigmentation, Albinism, Melanin Albinism INTRODUCTION For my research project I have chosen the genetic disease albinism. There are a few reasons why I chose albinism as my topic. First and foremost, in kindergarten I had a friend who was an albino, and although I have not seen him in over 10 years I am still curious as to what the causes of albinism are. Back then, my mother explained it to me by saying, thats just the way his skin is which is a fine way to explain it to a five year old, but now I find myself wanting to know more. Another reason I am curious about albinism actually extends from my first reason. I often wondered if there was any chance that my kids could possibly be born with it. I know now that it sounds a little bit ridiculous but I would sometimes worry that I wouldnt be able to take my children to the beach (I knew this because my friend from kindergarten could never come with us when we went in the summer). I also used to wonder whether or not my friend could see the same way I could, since his eyes looked so different from mine. As a result of all of this, I could not turn down the opportunity to research a disease that has held my curiosity for such a long time. PHENOTYPIC CHARACTERISTICS The most prominent phenotypic characteristic of albinism is obviously the lack of skin coloring. Albino skin is whitish in appearance, sometimes seeming to be almost translucent. Similarly, albino hair is also very pale, appearing closer to white than blonde. Albinism makes the skin extremely sensitive to sunlight. Albinos need to be very careful about exposure to the sun as they have a very high risk of burning due to lack of protection from ultraviolet rays, which is normally provided by the pigment melanin (2). Similar to the skin, albino eyes also lack color; the irises usually appear pinkish. People with albinism often have eye problems. First of all, they suffer from severe sensitivity to bright lights. Cases of extreme nearsightedness or farsightedness that cannot be completely corrected with eyeglasses are also common. People with albinism also sometimes demonstrate an involuntary back and forth movement of the eyes called nystagmus. Finally, people with albinism are more likely to develop astigmatism. It is possible to have albinism that affects the eyes without also affecting the skin. This is known as ocular albinism (3). INHERITANCE Albinism is an autosomal recessive disorder. All the children of two affected homozygous affected parents are also affected. This means that two parents who have albinism, and who possess two recessive alleles each for albinism will produce affected children 100% of the time. Being a relatively rare disorder, albinos are often the children of unaffected parents (this is the case with autosomal recessive disorders). Parents who are both heterozygotes (both carriers of the disease but not having it themselves) have a 75% chance of producing a normal, non-affected child. Because albinism is not carried on the sex chromosomes, it is expressed equally in both males and females, and either parent can transmit the disorder. Albinism also affects people of all races equally. Approximately 1 in 17,000 people has one of the types of albinism, which amounts to roughly 18,000 people in the United States (1). GENETIC AND CELLULAR ORIGINS Albinism is located on chromosome 11q 14-21. The gene associated with albinism is called OCA1 (among a few others). OCA1 codes for the protein tyrosinase. This protein is responsible for converting tyrosine into something called DOPA (dihydroxyphenylalanine). DOPA plays an important part in the formation of melanin by next becoming dopaquinone. Dopaquinone then forms black-brown eumelanin or red-yellow pheomelanin. Melanin is a pigment, the absence of which causes albinism (2). Albinism occurs when something causes the OCA1 gene to function improperly. This improper function disrupts the production of tyrosinase. With tyrosinase production malfunctioning, it is impossible for the body to make DOPA and as a result the body is also prevented from making melanin. The absence of melanin causes the lack of color in the skin of people who are affected with albinism (2). MOLECULAR ORIGINS The cDNA sequence for the OCA1 gene is 1607 bases long; 325 Adenine,

Darkness at Noon essays

Darkness at Noon essays Rubashov, himself an aging Bolshevik revolutionary and one of the few survivors from Lenin's old guard, is brought to a confrontation of his own past during his imprisonment and interrogation. The period is Stalin's Russia of the 1930s, a time when Stalin systematically eliminated all opposition to the new ideology of collectivism,' and his own rule. As a result, Rubashov is forced to undergo the same experience of suffering and psychological torture that he himself had been party to inflicting on many an innocent individual, including his own friends and even his lover, in the name of the revolution. This leads him to a great deal of introspection and soul searching on his personal value system and indeed, the ideology followed by the Party. Reflecting back on his own life, Rubashov slowly reaches the conclusion that the end does not justify the means. Now that Rubashov finds himself in the shoes of his own victims, he begins to re-examine the justification used by the Party in inflicting suffering on many individuals who betrayed even a hint of individualism or opposition to the cause. For instance, he recalls the case of Bogrov, a naval engineer: "advocatedsubmarineslarge range of action. The Party is in favor ofsmall rangenot have been enough to put him out of the wayhad to be discredited." (Koestler, 122) Slowly, Rubashov realizes just how much the Party has acted only in its own interests and not the interests of the masses. Truth and progress have no role to play. As Rubashov records in his diary, "leading agriculturistshot with thirty of his collaborators because he maintainednitrate artificial manure was superior to potash." (79). With imprisonment bringing Rubashov to the receiving end of the Party's policies, he realizes that he has spen...

DBM Business Law assignment Essay Example | Topics and Well Written Essays - 1000 words

DBM Business Law assignment - Essay Example Eventually Xavier never returned to buy the youngest kitten in the litter. This created problem to Zara for sale of the kittens as she did not engaged into transaction on the youngest kitten with anybody else. In order to manage the situation, Zara should have taken a token advance from Xavier for booking the youngest kitten for him. This could have brought commitment to the transaction process and Zara would have been able to manage the business situation in a tactful manner. In the second instance, another prospective buyer named Vic spoke to Zara over the telephone on the purchase of the kittens. After obtaining the details over phone, Vic informed Zara that he would enquire about the breed before taking a decision on purchase. During the telephonic conversation, Zara should note down the telephone number of Vic for any further communication. After due enquiry, Vic wrote a letter to Zara stating that he would purchase the eldest kitten. Later on he changed his mind and in order to cancel the order, Vic sent an email to Zara cancelling his intention of purchasing the kitten. Since the e-mail did not reach Zara due to server problem, Zara should carry on talking to other customers irrespective of Vic’s decision as she did not receive any communication from Vic. In case she had not been able to sell the kitten before the letter from Vic reached her, Zara should contact Vic for further transaction and then do the needful as per Vic’ latest decision. In the third case, another prospective buyer Yvonne sent an email to Zara that the price of 300 pound sterling is a bit higher for the Burmese breed and whether a price of 200 pound sterling would be acceptable to Zara. When Zara denied the proposal, Yvonne sent another email confirming to purchase the young Burmese kitten for the stated price. Zara in this case should reply by e-mail of the details about the young Burmese breed and the terms and conditions for sale. Zara should also offer Yvonne to mee t in person and look at the breed in order to strike a transparent deal for the sale of kittens. In the fourth scenario, Walter paid the stated price of 300 pound sterling to Zara and bought the kitten from her. At the time of sale of the kitten, Zara should provide all the details about the kitten and the terms and conditions of the sale of kitten. The kitten ate up furniture in Walters’ house which caused disappointment to Walter. When he saw a veterinary doctor, he said that the Burmese kitten was of a lower quality breed and actually a cross breed. Walter complained about the habits and quality of breed and wanted a refund from Zara. Zara should reiterate the details of the breed of Burmese kitten sold to Walter and explain her limitation and degree of accountability for the habits of the kitten post sale (Miller,  Jentz and  Cross, 2008, p.353). Advice to Amy Amy lives in village where her cousin also lives with her family. Amy is very much fond of his cousin who has run errands for Amy in the past. Amy lives alone in her house. Beryl undertook outdoor tasks for Amy in order to help her. Suddenly Charlie, who is the husband of Amy, lost his job. This put Beryl’s family into financial trouble. Beryl informed Amy about the loss of job of her husband, Charlie and also explained the financial difficulties that they were facing as a result of the incident. Beryl and Charlie also have a son named David who is exceptionally brilliant and puts little effort for achieving