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Crick And Watson: The Discover Essay, Research Paper

“Before the dawn of the 20th century, the central role played by one complicated molecule in the shape of all living things was one of nature’s best-kept secrets.” (The History 100) “DNA (Deoxyribonucleic Acid), is the nucleic acid found in the nuclei of all cells. It is considered as a gene.” (Webster’s Dictionary 257) Before the year of 1953, no one knew that DNA was going to be “the great architect of life” (The Histroy 100). It was two intelligant men that discovered natures secret, James Watson and Francis Crick. These men were what helped us understand how genetic information could be stored in the chemical molecule called, DNA. Because of Crick and Watson we know today that, the structure of DNA is the most important scientific discovery of the 20th century.

Francis Crick came from Physics and James Watson came from Genetics. Neither of these two men had experience in the research of the chemical and physcial analysis of crystals (DNA). They first met in Octobre of 1951, which is now considered “One of the greatest dialogues in the history of science.” (Discovery of 26) Almost immediately, each realized that the other was thinking about DNA, genes, and heredity. ” There has to be an extraordinary interaction between two people, before the mind can do what they did. Jim and Francis talked in half sentences. They understood each other amost without words…that marvelous resonance between two minds – that high state in which one plus one does not equal two, but more like ten.” (Discovery of 26) Watson thought meeting Crick was remarkable. He had actually found someone who “knew that DNA was more important than protein.” (Discovery of 26)

After studying early X-ray diffraction, James and Francis discovered that the nucleic acids were constructed as a helix. Working with the knowledge that chromosomes form replicas during cell division and that a chromosome was believed to be a string of DNA molecules, they concluded that the DNA molecule must form a replica of itself. By 1953 Watson and Crick had determined that the structure of DNA was a complimentary double helix. They showed that each single helix of DNA served as a model for its complimentary helix and that the two resultant strains unwound from the double helix during replication of the cell. The two intertwined sugar phosphates chains connected like steps with the flat base pairs, adenin-thymine and guanine-cytosine. Their findings opened the door to the many advances that we see today and we will continue to see even more possibilities in the future.

The words DNA, have been heard very often these days. We hear it in the news that some criminals have their DNA tested against the evidence found in the crime of the scene, we see it in films like the “Jurassic Park”, and cloning is all about DNA.

In the Law enforcement area, DNA fingerprinting has been used effectively to link suspects to evidence found at the crime scenes, such as hair, blood or saliva. The sample taking is then segmented using enzymes and the segments are arranged by size using a process called electrophoresis. The segments are marked with probes and exposed on X-ray film, where they form a pattern of black bars. This is the DNA fingerprint. If the DNA fingerprints produced from two different samples match, the samples probably came from the same person.

DNA fingerprinting was first developed as an identification technique in 1985. Before this it was used to detect the presence of genetic diseases. It soon came to be used in criminal investigations and forsenic medicine. DNA fingerprints obtained from evidence collected at the crime scene are compared to the DNA fingerprints of the suspects. The DNA evidence can either implicate or exonerate a suspect.

Generally courts have accepted the reliability of DNA testing and admitted DNA test results into evidence. However, DNA fingerprinting is contraversial in a number of areas: the cost of testing and the possible misuse of the technique.

The accuracy of DNA fingerprinting has been challenged for several reasons. First, because DNA segments rather than complete DNA strands are “fingerprinted,” a DNA fingerprint may not be unique; large scale research to confirm the uniqueness of DNA fingerprinting test results has not been conducted. Also, DNA fingerprinting is often done in private laboratories that may not follow uniform testing standards and quality control. Furthermore, since humans must interpret the test, human error could lead to false results.

Widespread use of DNA testing for identification purposes may lead to the establishment of a DNA fingerprint database. This database could potentially be used in unauthorized purposes, such as identifying individuals with illnesses such as Acquired Immune Deficieny Syndrome (AIDS).

DNA can also be used as personal identification. Since everybody has different DNA, it is impossible to forge it. In fact, the Army has begun to collect DNA fingerprints from all personnel for uses such as identification casualties or MIAs. It is also used to settle paternal disputes over children for child support.

In the medical field, DNA analysis can be used to diagnose inherited diseases such as Cystic Fibrosis, Hemophilia, Huntington’s disease, Alzheimer disease, Sickle Cell Anemia, Thalassemia and others. Upon dectation of these diseases, the DNA analysis can provide the medical experts with valuable information to provide counseling for the families with a history of the inherited disorder. Besides counseling families, DNA anaylsis can also be used for developing cures for inherited disorders.

Cloning, which is all about DNA, has been the talk everywhere around the world lately. “It is done by taking a whole nucleus, containing an entire set of Chromosomes from a cell and injecting it into a fertilized egg whose own nucleus has been removed. The devision of the egg brings about the devision of the nucleus and the descendant nuclei can, in their turn, be injected into eggs. After several such transfers, the nuclei may become capable of directing the development of the eggs into complete new organisms genetically identical to the organism from which the original nucleus was taken. This clonig technique is thus, in theory, capable of producing large number of genetic identical individuals.” (Clone, Microsoft Encarta)

There are many good and bad point to cloning. The failure rate is enormous. On average, only just over one percent of attempts actually result in a live birth. The first cloned mammal was Dolly the sheep. It took more than 250 attempts before Dolly was born. There are some animals which, unlike the sheep and cattle, scientist have never managed to clone, despite repeated attempts. These include primates, which suggest that human cloning may be nigh-on impossible using current methods. However, Professor Ian Wilmut, from the Roslin Institute, has been approached by people asking whether or not he can help them clone a human. His response in a meeting was, “It is quite obvious to me that it is appalling for anyone to suggest using this on a women at the present time. I think you have to be ill to use this on humans.” ( ) In fact, he thinks that he would disapprove of any use of human cloning techniques to actually create a new person. For example, to assist in infertility or replace a lost relative. Although, in the future he sees genetic techniques such as these as a possible source of hope to people with certain illnesses. “It could be helpful to treat conditions associated with damage to cells which don’t repair themselves – there isn’t currently an effective treatment for any of them.” ( ) Diseases in this catagory include Parkinson’s, diabetes, liver damage, arthritis and macular degeneration, which can lead to blindness. In each of these cases doctors might be able to use cloned stem cells.

This technique would involve taking of cells from the disease sufferer and using the genetic code inside to clone an embryo. This would contain stem cells, which can, depending on their environment, progress to become hundreds of different types of cells, each with a different function, such as brain neuron cells or special pancreas cells which diabetics lack.

Scientist want to clone embryos for research. The Stem cells, in theory, can be growen “in vitro”, ensuring a ready supply. They can also be inserted at the disease site and hopefully replace the lost cells. In Parkinson’s, the patient lacks cells which produce a brain chemical called dopamine. If these are replaced, then in theory the symptoms and decline could be halted. For this purpose Professor Wilmut said “I, personally, would be willing to think about doing this for this purpose.” ( ) There are other avenues in which genetic advances could produce viable treatments. The Rosalin Institute has already made genetic modification to sheep which make them produce a protein in their milk that helps clot human blood. This could eventually help hemophiliacs, who lack the protien.

Cloning calfes have surprised scientist by tapping into the fountain of youth. It seems that their cells are younger then those from which they were cloned. The result is enormously encouraging for hopes of growing and making organs for transplant because it means that, in principle, fresh young organs could be gowen from old, tired ones. The reason why scientist were so surprised was because early experiments, such as the lamb Dolly, had suggested that this would be impossible. Dolly’s cells, taken from an adult ewe, were old before their time.

Why the calfs that were cloned are so different, scientists have no idea. They were cloned from fibroblasts that are found in structural tissues, including cartilage and bone. Dr. Robert Lanza of ACT said “The amazing thing is that all six heifers have cells younger than their chronological age. When we took cells from the cloned heifers and then grew them in the culture, they lived twice as long as normal. Even more amazing, when we took skin cells from them and measured the activity of a gene which is active in young cells, but declines with age, we found that its activity was up to five times normal.” ( ) The results show that cloning actually has the potential to reverse the ageing of cells. This has profound implications for treating age-related diseases and for understanding the actual mechanisms behind the ageing processe.

If the calfs do live longer then usual, it could mean that humans could potentially live for 200 years. Also, they would not develop the chronic disease of old age until they were 150.

Scientist have began to realize that DNA may exist in ancient tissue. This has gave them hope to catch evolution. Due to the advances in in moleculer biological techniques, DNA has been extracted from a wide variety of remains including bones, teeth, shells and amber ranging in age up to 45,000 years.

The ability to study DNA from archaelogical finds with PCR opens up:

“The possibility of studying molecular evolution by actually going back in time and directly approaching DNA sequences that are ancestral to their present day counter parts. Therefore, the relationship of extinct species to extant species can be adressed.

Evolution of populations, the comparison of ancestral and descendant populations can be studied by attributing changes in gene frequencies to factors like variations in population size, migration, selestion and genetic drift.

Ability to monitor fast genetic processes such as recombinational events, for example in human parasites (especially viruses) and the evolution of domestic plants.

However, this young field of molecular archeology has to overcome some problems because like all macromolecules extracted from old tissues remains, ancient DNA is heavily modified. Therefore, the goal is for the future is to refine PCR” ( )

Also, the recent advances in DNA-based technologies increase the likelihood for molecular genetic techniques to positvely affect plant breeding in developing countries, as well as in the well-equipped genetic engeneering labroatories in developed countries. The use of linked DNA markers makes it possible for the first time large scale application of indirect selections for important agronomic traits. This project helps ensure multinational co-operations for transferring modern biotechnology to developing countries with the active participation of leading labrotories.

Although, James Watson, “the Father of DNA revolution” ( ) spoke of his fears that “luddites” who oppose genetically modified food and crops could make Britain’s agriculture falter and scientists flee.

Watson, who has been a regular visitor to Britain sicne he discovered the structure of DNA, fears the country will go regressive if the Government bows to a green movement that he characterises as resistent to change, fond of bans and anit-scientific. “They tend to be ideological, intolerant and uniterested in the facts. It is another form of fundamentalism.” ( )

Watson has been dismayed by the strength of public emotion, blaming it on the green movement and the leagacy of distrust left by the BSE fiasco. “If Europe rejects science in its agriculture, it will marginalised.” ( ) European nations would see their young scientist “go the the States because that is where the action is”. ( )

The distinguised scientist is more then happy to eat genetically modified food: “I have absolutely no anxiety. The only person harmed so far by DNA is President Clinton. I am worried about a lot of things, but not modified food.” ( )

When Watson and Crick unraveled the mystery of the double helix, they brought about a revolution in biology. Scientist now have a completely new way of thinking about living organisms. “The goal of using chemistry and physics to understand life has been attained.” (Discovery of 105) People no longer have to wonder how their child has blond hair or who the father is. With the help of DNA and cloning, many disease in the future, could be cured or put to a halt. Also cloning could be a way to a person’s perfect donor organ. There may be no risks of dying while waiting. Just think of all the possibilites. Years from now we could extact DNA when humans are born and if ever needed, reproduce organs, not humans, mind you. Since DNA, the Law enforcement have had it easier in finding their suspects because of DNA fingerprinting. DNA allows us to go back 45,000 years and learn about the people from centuries ago. It is unbelieveable the things that society today can do and it is all because of two men, Watson and Crick. They discovered what is the most important discovery since the 20th century, DNA.

“Before the dawn of the 20th century, the central role played by one complicated molecule in the shape of all living things was one of nature’s best-kept secrets.” (The History 100) “DNA (Deoxyribonucleic Acid), is the nucleic acid found in the nuclei of all cells. It is considered as a gene.” (Webster’s Dictionary 257) Before the year of 1953, no one knew that DNA was going to be “the great architect of life” (The Histroy 100). It was two intelligant men that discovered natures secret, James Watson and Francis Crick. These men were what helped us understand how genetic information could be stored in the chemical molecule called, DNA. Because of Crick and Watson we know today that, the structure of DNA is the most important scientific discovery of the 20th century.

Francis Crick came from Physics and James Watson came from Genetics. Neither of these two men had experience in the research of the chemical and physcial analysis of crystals (DNA). They first met in Octobre of 1951, which is now considered “One of the greatest dialogues in the history of science.” (Discovery of 26) Almost immediately, each realized that the other was thinking about DNA, genes, and heredity. ” There has to be an extraordinary interaction between two people, before the mind can do what they did. Jim and Francis talked in half sentences. They understood each other amost without words…that marvelous resonance between two minds – that high state in which one plus one does not equal two, but more like ten.” (Discovery of 26) Watson thought meeting Crick was remarkable. He had actually found someone who “knew that DNA was more important than protein.” (Discovery of 26)

After studying early X-ray diffraction, James and Francis discovered that the nucleic acids were constructed as a helix. Working with the knowledge that chromosomes form replicas during cell division and that a chromosome was believed to be a string of DNA molecules, they concluded that the DNA molecule must form a replica of itself. By 1953 Watson and Crick had determined that the structure of DNA was a complimentary double helix. They showed that each single helix of DNA served as a model for its complimentary helix and that the two resultant strains unwound from the double helix during replication of the cell. The two intertwined sugar phosphates chains connected like steps with the flat base pairs, adenin-thymine and guanine-cytosine. Their findings opened the door to the many advances that we see today and we will continue to see even more possibilities in the future.

The words DNA, have been heard very often these days. We hear it in the news that some criminals have their DNA tested against the evidence found in the crime of the scene, we see it in films like the “Jurassic Park”, and cloning is all about DNA.

In the Law enforcement area, DNA fingerprinting has been used effectively to link suspects to evidence found at the crime scenes, such as hair, blood or saliva. The sample taking is then segmented using enzymes and the segments are arranged by size using a process called electrophoresis. The segments are marked with probes and exposed on X-ray film, where they form a pattern of black bars. This is the DNA fingerprint. If the DNA fingerprints prorole played by one complicated molecule in the shape of all living things was one of nature’s best-kept secrets.” (The History 100) “DNA (Deoxyribonucleic Acid), is the nucleic acid found in the nuclei of all cells. It is considered as a gene.” (Webster’s Dictionary 257) Before the year of 1953, no one knew that DNA was going to be “the great architect of life” (The Histroy 100). It was two intelligant men that discovered natures secret, James Watson and Francis Crick. These men were what helped us understand how genetic information could be stored in the chemical molecule called, DNA. Because of Crick and Watson we know today that, the structure of DNA is the most important scientific discovery of the 20th century.

Francis Crick came from Physics and James Watson came from Genetics. Neither of these two men had experience in the research of the chemical and physcial analysis of crystals (DNA). They first met in Octobre of 1951, which is now considered “One of the greatest dialogues in the history of science.” (Discovery of 26) Almost immediately, each realized that the other was thinking about DNA, genes, and heredity. ” There has to be an extraordinary interaction between two people, before the mind can do what they did. Jim and Francis talked in half sentences. They understood each other amost without words…that marvelous resonance between two minds – that high state in which one plus one does not equal two, but more like ten.” (Discovery of 26) Watson thought meeting Crick was remarkable. He had actually found someone who “knew that DNA was more important than protein.” (Discovery of 26)

After studying early X-ray diffraction, James and Francis discovered that the nucleic acids were constructed as a helix. Working with the knowledge that chromosomes form replicas during cell division and that a chromosome was believed to be a string of DNA molecules, they concluded that the DNA molecule must form a replica of itself. By 1953 Watson and Crick had determined that the structure of DNA was a complimentary double helix. They showed that each single helix of DNA served as a model for its complimentary helix and that the two resultant strains unwound from the double helix during replication of the cell. The two intertwined sugar phosphates chains connected like steps with the flat base pairs, adenin-thymine and guanine-cytosine. Their findings opened the door to the many advances that we see today and we will continue to see even more possibilities in the future.

The words DNA, have been heard very often these days. We hear it in the news that some criminals have their DNA tested against the evidence found in the crime of the scene, we see it in films like the “Jurassic Park”, and cloning is all about DNA.

In the Law enforcement area, DNA fingerprinting has been used effectively to link suspects to evidence found at the crime scenes, such as hair, blood or saliva. The sample taking is then segmented using enzymes and the segments are arranged by size using a process called electrophoresis. The segments are marked with probes and exposed on X-ray film, where they form a pattern of black bars. This is the DNA fingerprint. If the DNA fingerprints pro average, only just over one percent of attempts actually result in a live birth. The first cloned mammal was Dolly the sheepcentral. It took more than 250 attempts before Dolly was born. There are some animals which, unlike the sheep and cattle, scientist have never managed to clone, despite repeated attempts. These include primates, which suggest that human cloning may be nigh-on impossible using current methods. However, Professor Ian Wilmut, from the Roslin Institute, has been approached by people asking whether or not he can help them clone a human. His response in a meeting was, “It is quite obvious to me that it is appalling for anyone to suggest using this on a women at the present time. I think you have to be ill to use this on humans.” ( ) In fact, he thinks that he would disapprove of any use of human cloning techniques to actually create a new person. For example, to assist in infertility or replace a lost relative. Although, in the future he sees genetic techniques such as these as a possible source of hope to people with certain illnesses. “It could be helpful to treat conditions associated with damage to cells which don’t repair themselves – there isn’t currently an effective treatment for any of them.” ( ) Diseases in this catagory include Parkinson’s, diabetes, liver damage, arthritis and macular degeneration, which can lead to blindness. In each of these cases doctors might be able to use cloned stem cells.

This technique would involve taking of cells from the disease sufferer and using the genetic code inside to clone an embryo. This would contain stem cells, which can, depending on their environment, progress to become hundreds of different types of cells, each with a different function, such as brain neuron cells or special pancreas cells which diabetics lack.

Scientist want to clone embryos for research. The Stem cells, in theory, can be growen “in vitro”, ensuring a ready supply. They can also be inserted at the disease site and hopefully replace the lost cells. In Parkinson’s, the patient lacks cells which produce a brain chemical called dopamine. If these are replaced, then in theory the symptoms and decline could be halted. For this purpose Professor Wilmut said “I, personally, would be willing to think about doing this for this purpose.” ( ) There are other avenues in which genetic advances could produce viable treatments. The Rosalin Institute has already made genetic modification to sheep which make them produce a protein in their milk that helps clot human blood. This could eventually help hemophiliacs, who lack the protien.

Cloning calfes have surprised scientist by tapping into the fountain of youth. It seems that their cells are younger then those from which they were cloned. The result is enormously encouraging for hopes of growing and making organs for transplant because it means that, in principle, fresh young organs could be gowen from old, tired ones. The reason why scientist were so surprised was because early experiments, such as the lamb Dolly, had suggested that this would be impossible. Dolly’s cells, taken from an adult ewe, were old before their time.

Why the calfs that were cloned are so different, scientists have no idea. They were cloned from fibroblasts that are found in structural tissues, including cartilage and bone. Dr. Robert Lanza of ACT said “The amazing thing is that all six heifers have cells younger than their chronological age. When we took cells from the cloned heifers and then grew them in the culture, they lived twice as long as normal. Even more amazing, when we took skin cells from them and measured the activity of a gene which is active in young cells, but declines with age, we found that its activity was up to five times normal.” ( ) The results show that cloning actually has the potential to reverse the ageing of cells. This has profound implications for treating age-related diseases and for understanding the actual mechanisms behind the ageing processe.

If the calfs do live longer then usual, it could mean that humans could potentially live for 200 years. Also, they would not develop the chronic disease of old age until they were 150.

Scientist have began to realize that DNA may exist in ancient tissue. This has gave them hope to catch evolution. Due to the advances in in moleculer biological techniques, DNA has been extracted from a wide variety of remains including bones, teeth, shells and amber ranging in age up to 45,000 years.

The ability to study DNA from archaelogical finds with PCR opens up:

“The possibility of studying molecular evolution by actually going back in time and directly approaching DNA sequences that are ancestral to their present day counter parts. Therefore, the relationship of extinct species to extant species can be adressed.

Evolution of populations, the comparison of ancestral and descendant populations can be studied by attributing changes in gene frequencies to factors like variations in population size, migration, selestion and genetic drift.

Ability to monitor fast genetic processes such as recombinational events, for example in human parasites (especially viruses) and the evolution of domestic plants.

However, this young field of molecular archeology has to overcome some problems because like all macromolecules extracted from old tissues remains, ancient DNA is heavily modified. Therefore, the goal is for the future is to refine PCR” ( )

Also, the recent advances in DNA-based technologies increase the likelihood for molecular genetic techniques to positvely affect plant breeding in developing countries, as well as in the well-equipped genetic engeneering labroatories in developed countries. The use of linked DNA markers makes it possible for the first time large scale application of indirect selections for important agronomic traits. This project helps ensure multinational co-operations for transferring modern biotechnology to developing countries with the active participation of leading labrotories.

Although, James Watson, “the Father of DNA revolution” ( ) spoke of his fears that “luddites” who oppose genetically modified food and crops could make Britain’s agriculture falter and scientists flee.

Watson, who has been a regular visitor to Britain sicne he discovered the structure of DNA, fears the country will go regressive if the Government bows to a green movement that he characterises as resistent to change, fond of bans and anit-scientific. “They tend to be ideological, intolerant and uniterested in the facts. It is another form of fundamentalism.” ( )

Watson has been dismayed by the strength of public emotion, blaming it on the green movement and the leagacy of distrust left by the BSE fiasco. “If Europe rejects science in its agriculture, it will marginalised.” ( ) European nations would see their young scientist “go the the States because that is where the action is”. ( )

The distinguised scientist is more then happy to eat genetically modified food: “I have absolutely no anxiety. The only person harmed so far by DNA is President Clinton. I am worried about a lot of things, but not modified food.” ( )

When Watson and Crick unraveled the mystery of the double helix, they brought about a revolution in biology. Scientist now have a completely new way of thinking about living organisms. “The goal of using chemistry and physics to understand life has been attained.” (Discovery of 105) People no longer have to wonder how their child has blond hair or who the father is. With the help of DNA and cloning, many disease in the future, could be cured or put to a halt. Also cloning could be a way to a person’s perfect donor organ. There may be no risks of dying while waiting. Just think of all the possibilites. Years from now we could extact DNA when humans are born and if ever needed, reproduce organs, not humans, mind you. Since DNA, the Law enforcement have had it easier in finding their suspects because of DNA fingerprinting. DNA allows us to go back 45,000 years and learn about the people from centuries ago. It is unbelieveable the things that society today can do and it is all because of two men, Watson and Crick. They discovered what is the most important discovery since the 20th century, DNA.


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