Dna Research Paper

Dna Research Paper
The discovery of DNA began in 1928 when the British bacteriologist Frederick Griffith was performing an experiment with mice based on
pneumococcus, a bacterium that causes pneumonia in humans. This bacterium has a capsule made of polysaccharides that has a shiny and smooth
appearance, called s–strain. There are mutants of s–strain that do not produce this capsule and form a rough–looking colony called r–strain. Griffith
discovered that this mutant did not kill the mice, but if pneumococcus R was mixed with pneumococcus S, the mice would die; this shows that the
s–strain contained something capable of transforming R bacteria into pathogens.
Oswald Avery with his colleagues Collin Macleod and Maclin McCarty began to separate the S bacteria...show more content...
At the 1950s Rosalind Franklin was the first woman to obtain an excellent DNA photography using x–ray diffraction. With this photograph she was
able to deduce the distribution and distance of the atoms that make up the DNA. Then Janes Watson and Francis Crick had in mind several models of
the DNA molecule, but having no type of description they did not know which model was the correct one; The photograph of Franklin was key for
Watson and Crick to conclude that the DNA model should have a double helix structure, they also calculated the exact distances between the atoms and
the chains that make up the DNA. This provided answers to many questions about genetics background.
The DNA or deoxyribonucleic acid it's an acid of the nucleus of the cells, where the genetic information is found, it is used in the development and
functioning of any living organism and of some viruses. This molecule is responsible for storing information, DNA can be compared as a plan, a code
or a recipe, because it contains the instructions needed to build cells and their components, such as proteins and RNA molecules.
The DNA molecule is a double chain of nucleotides that can be divided into ВЁbytesВЁ of information, that we call genes, and each of these genes
come together to create a specific protein. These proteins are those that
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DNA Profiling Essay example
From cases such as OJ Simpson to Chandra Levy, DNA profiling also called DNA fingerprinting or DNA typing has played a major role in the
criminal justice system. The law enforcement community uses DNA profiling to rule out or identify suspects. Unlike hair microscopy, bite mark
comparisons, shoe print comparisons, and firearm tool mark analysis, DNA typing has been developed through massive scientific research and has
undergone meticulous scientific evaluation (Innocence Project). DNA is a foolproof method of identifying a perpetrator of a crime.
Like fingerprints, DNA is unique, with the exception of identical twins; no two people have the same DNA. DNA profiling is a technique that can
identify the person responsible of a violent...show more content...
With over three million base pairs in the human gene, forensic scientists are able to distinguish a person's genetic makeup.
. DNA profiling was first introduced to the criminal justice field in the mid–1980's (DNA Initiative). DNA profiling was first described in 1984 by Alec
Jeffreys, a geneticist at the University of Leicester in Britain (Aronson, 7). Dr. Jeffreys found that the genes that have no function, called "junk DNA"
is where most of the variation is used for DNA profiling (Aronson 9). This region contains DNA sequences that repeat over and over again. Alec
Jeffreys determined that the number of repeated sections at different locations vary from individual to individual (DNA Initiative). Consequently these
repetitive regions became known as "variable number of tandem repeats" or VNTR's.
RFLP or restriction fragment length polymorphisms became the first scientifically accepted DNA analysis method in the United States (Jones). The
repeat segments are cut out of the DNA strand by a restrictive enzyme that acts like scissors and the resulting fragments are sorted out by
electrophoresis (Saferstein 391). However, there are some drawbacks using the RFLP method in the forensic science community. The RFLP technique
requires a large amount of DNA and must be of high quality and cannot be degraded (Jones). Forensic scientists and the law enforcement community

Dna Essay
Abstract
This paper explores the history and some interesting facts about DNA. The last couple centuries have seen an exponential growth in our knowledge of
DNA. The history of the DNA can be traced back to multiple devoted scientist. This article attempts to summarize, and review the basic history ofDNA
while providing some fascinating information about it.
A Brief Historic Review Throughout the early 19th and 20th century, many scientists have studied deoxyribonucleic acids in order to attain higher
understanding over the matter. Johann G. Mendel had figured out and understood the laws of heredity. Friedrich Miescher amazingly discovered DNA
in 1869, even though scientists did not understand DNA was the genetic material...show more content...
The pictures were shown to James Watson andFrancis Crick by Maurice Wilkins. They were then able to confirm their theory about the 3D structure
of DNA. In 1962, they were awarded the Nobel Prize in Physiology or Medicine for solving the structure of DNA. The Nobel committee could not
award it to Franklin because the Nobel prize could only be shared by three people and also because she was already dead (DNA from the Beginning,
2011)
Origin of the Four Bases' Names The four names of the nitrogenous bases of the DNA are adenine, thymine, guanine, and cytosine. The word
"adenine" was created in the 19th century in German from the Greek words "adД“n" "gland" and "in". The word "cytosine" was coined in the 19th
century from the German word "cytosin" from cyto– "cell", –ose and the chemical suffix –ine. The word "guanine" comes from the English words
"guano" and "ine" and was also created in the 19th century. The word "thymine" comes from words "thymus" and the suffix –ine.
Interesting Facts Although DNA molecules seem minuscule, if all the DNA in a human body was unwound and placed from end to end, it would
cover about 10 billion miles. That's approximately the same distance as traveling from the Earth to Pluto and back. (Helmenstine, 2017). "If a person
typed 60 words per minute, eight hours a day, it would take approximately 50 years for them to type the human genome" (Kawasaki, 2010). Scientist
have calculated that DNA has a 521–year half–life, which

DNA Essay example
DNA is a term that has been used in science as well as in many parts of daily life. The general public knows that DNA is a part of our bodies but
they may wonder what exactly is DNA? DNA is a term used for deoxyribonucleic acid and it is the genetic material of all organisms, it is the
molecule of life and it determines all of our physical characteristics. DNA is present in every single form of life. More than 50 years after the science
of genetics was established and the patterns of inheritance were clarified, the largest questions remained unanswered: How are the chromosomes and
their genes copied exactly from cell to cell, and how do they direct the structure and behavior of living things?
Two American geneticists, George...show more content...
"To make a new, identical copy of the DNAmolecule, the two strands unwind and separate at the bases which are weakly bound; with more
nucleotides available in the cell, new complementary bases can link with each separated strand, and two double helixes result." (Caldwell) Since the
"backbone" of every chromosome is a single long, double–stranded molecule of DNA, the production of two identical double helixes will result in the
production of two identical chromosomes.
The DNA backbone is actually longer than the chromosome but is tightly coiled up within it. This packing is now known to be based on minute
particles of protein known as nucleosomes, that can only be seen under the most powerful electron microscope. The DNA is wound around each
nucleosome to form a beaded structure.
The structure is then further folded so that the beads associate in regular coils. Thus, the DNA has a "coiled–coil" configuration.
After the discoveries of Watson andCrick, the question that remained was how the DNA directs the formation of proteins, compounds central to all the
processes of life. Proteins are not only the major components of most cell structures, they also control virtually all the chemical reactions that occur in
living matter. The ability of a protein to act as part of a structure, or as an enzyme affecting the rate of a particular chemical reaction, depends on its
molecular shape. This shape, in turn,

Essay On Dna Profiling
Aram, a 16–year–old trainee hairdresser from Keyworth in Nottinghamshire, was abducted, raped and strangled on 30 October 1983 – five years before
the careless driver was born. (Her murder was featured in the first ever episode of Crimewatch in 1984.) The police had a few circumstantial leads to
go on: a stolen red Ford Fiesta; a handwritten message from the killer saying they'd never catch him; a paper towel recovered from the toilet of a pub,
the Generous Briton, where shortly after the murder a man with blood under his fingernails had eaten a ham sandwich, drunk a pint of orange juice and
lemonade, and told the landlady an unlikely story about having driven up the M1 to see some friends who weren't in. Twenty thousand people were
interviewed in the course of the investigation, but the killer...show more content...
This is however a misconception since DNA can potentially provide more information about a person than a fingerprint and thus can open the door
more widely to breaches of privacy. The DNA of a person can be used to tell law enforcement that you have a brother or that you were adopted. It can
also identify by ethnicity or sex or reveal whether you predisposed to serious diseases such as cancer and tendencies to violence, substance abuse or
mental illness.
Currently, the DNA examined and recorded for forensic purposes does no reveal the most personal of these details but the technology for doing this
exists or is likely to exist in the future. The ability to use DNA to make family connection is currently the main issue raised by the use of DNA
technology in law enforcement, which is bound to result in futuristic invasion of privacy or possible harassment of those who happen to be family
members of possible

DNA Extraction Essay
DNA Extraction
In extracting chromatin from the cells of wheat germ there are seven steps to
follow. The optimal cell to use would be the polyploidal eukaryotic. Eukaryotes
have nucleus membrane–bound organelles, while prokaryotic does not. The
polyploidal eukaryotic cell has DNA that is held in the nucleus while the
prokaryote has DNA that floats freely around the cell. The DNA of eukaryotes is
more complex and extensive than the other. Prokaryote is a bacterial cell that
usually has DNA in one large strand and only has one chromosome while the
eukaryotic cell has more than one chromosome and is considered to be a higher
organism. Prokaryotes have an outer wall that prevents them from bursting or...show more content...
The
baking soda must keep the pH levels at a neutral place similar to the way pool
chemicals work together. If we didn't buffer the solution we would end up with
trash. Next you add the meat tenderizer. I did further research and found

that the "hydrolyzing protein (enzyme) known as papain can either be used as
trace metal carrier or a sequestering agent that reacts with ions to form soluble
complexes."2 Both temperature and pH can bring about a change in polypeptide
shape. When a protein loses it normal configuration it is called denatured. The
tenderizer must eliminate the proteins, the membrane and envelope allowing the
DNA to free itself from the tight coil. In the last step, you add ice–cold alcohol.
When you add the freezing alcohol to the hot test tube you will cause
precipitation . Water is a polar molecule and when mixed with alcohol
the ethanol's reaction with the DNA changes it from a polar to a nonpolar state.
Therefore, it is stuck between two polar liquids and it forms its own layer.
The DNA is not soluble in the alcohol unlike the soap. Only the DNA that directly
contacts the alcohol becomes nonpolar and is near the top can precipitate out of
the detergent but stay under the alcohol, where it is not soluble and therefore you
can see the strand of DNA. There are three steps that were completed:
homogenization, deprotenization, and precipitation of the DNA.

DNA testing Essay
DNA testing has overthrown the way police collect evidence in a number of criminal cases, especially rape and murder and consequently had a large
impact on many past cases. However there are many disadvantages to DNA testing, such as a challenge of accuracy, the costs of DNA testing and the
possible misuse of DNA. The prospect of a national DNA database in Australia has been heavily criticised withcomplaints of invasion of privacy and
stigma against those with terminal diseases.
Deoxyribonucleic acid, or DNA as it is most commonly known, is a strand of molecules found within the cell nucleus of all living things. It is called a
"genetic fingerprint" because each is different to the other and everyone, apart from identical twins, have...show more content...
Another downside to the use of DNA is the misuse of results. Victims with AIDS feel that they might be stigmatised if their DNA is stored in a
national database and it could be used against them.
The prospect of a genetic database in Australia has been raised recently. The federal police are pushing for a national database to help solve crime
and are asking for legislation to be allowed to collect DNA samples from people accused, or suspected of committing an offence (the Australian,
06.12.1997 see appendix one)
The proposal has sparked a moral dilemma. Victoria has had a DNA database since 1992 with the reasoning that, if a suspect is cleared, their DNA
must be erased off the list. However, recently Victorian government has allowed police to collect samples from more suspected criminals, not just
those accused of murder, serious assault or rape. Now they are allowed to collect from those accused of drug trafficking, arson causing death and
aggravated burglary.
Privacy is also another big issue surrounding the plans for a database. Chairman of the New South Wales privacy council says that the prospect of a
genetic database is a "cavalier disregard for people's privacy"
Recently it was passed that all states, apart from Western Australia have the right to compose a DNA database (The Sydney Telegraph, 22.04.2001 see
appendix two) and already there had been a few flaws found. With

Essay on Molecular Genetics
1. DNA Nucleotide
[pic]
Nucleotides consist of three parts ––– a pentose sugar, a nitrogen–containing base, and a phosphate group. A pentose sugar is a five–sided sugar.
Deoxyribose has a hydrogen atom attached to its #2 carbon atom (designated 2'), and ribose has a hydroxyl group atom there. Deoxyribose–containing
nucleotides are the monomers of DNA
RNA Nucleotide
[pic]
The left picture shows the nucleotide unit of RNA. Nucleotides differ from nucleosides in that they have phosphate groups. Nucleotides can exist in the
mono–, di–, or tri–phosphorylated forms. The most common site of phosphorylation of nucleotides found in cells is the hydroxyl group attached to the
5'–carbon of the ribose....show more content...
This gives RNA the unique ability to assume different shapes and functions. Though DNA performs the more important part of laying down the
benchmark and determines genetic characteristics. In simple terms we could see DNA as having two strands, while RNA has a single one. Thus we
can see that the two have a symbiotic relationship but different destinies. They are both critically important, yet evolve differently.Deoxyribose sugar in
DNA reacts less on account of C–H bonds. It is stable in Alkalaine conditions, as DNA contains smaller grooves where the damaging enzymes can get
attached, which makes it difficult for these to attack it. Ribose sugar on the other hand is more reactive because of C–OH (hydroxyl bonds). It is not at
all stable in alkaline conditions, as RNA has larger grooves, which makes it vulnerable to attacks by enzymes. B form defines the helix geometry of
DNA. The body destroys enzymes that cling to DNA. It can be though damaged by exposure to ultra violet rays.
Both DNA and RNA are nucleic acids, but have a few basic differences, as explained above. Unlike DNA, RNA structures do not consist of
self–complementary sequences that allow parts of the RNA to fold and form its own pairs and make double. They in fact consist of short helices
packed together into protein like structures.

2. DNA Replication
The original DNA unwinds and unzips then the DNA polymerase hooks up with the DNA

Essay On DNA Protein
Dr Sleeman – "From DNA to secreted protein: describe the key molecular events required and their organisation within the cell"
The genome, all the genetic material encoded within the sequence of deoxyribonucleic acid (DNA), which is unique to each individual organism, has
all the information required for a cell to sustain life. This is possible due to gene expression which is the process of the genetic code, DNA, being
translated into proteins which a cell can then utilise for specific functions whether it be a unicellular or multicellular organism. Through this process
there are many steps taken from the raw genetic code to the finished protein, the cell ensuring each step progresses without mistake and that the
resulting protein has been...show more content...
2017.). This is shown in figure 1. A eukaryotic organism can also have promoters and repressors, though there are more ways in which a gene can be
regulated. For instance, DNA in eukaryotic organisms binds tightly to histones, a type of protein, and this forms chromatin. Depending on how
decondensed the chromatin is can affect how easily the gene can be transcribed (www.ncbi.nlm.nih.gov. 2017.). Processes such as these are needed
throughout all branches of life, and once a gene is no longer being repressed it can then be transcribed.
Transcription is the copying of a strand of DNA, called the template strand, to form single–stranded messenger ribonucleic acid (mRNA).
Figure 2 – Transcription
(Gary E. Kaiser (May 26, 2001) Fig. 4: Transcription of mRNA Complementary to a Gene)
Illustrated in figure 2 is transcription, which is broken down into three stages. First the RNA polymerase binds to the DNA at a promoter region, this
promoter region contains sequences which allow binding of the RNA polymerase. The second stage of transcription is elongation, as the DNA is
unwound the RNA polymerase forms the singled stranded mRNA molecule. Like with DNA, the RNA is made of nucleotide bases with the exception
that instead of thymine there is uracil. As the RNA polymerase forms the mRNA, complementary bases pair up guanine with

The Discovery of DNA Essay
DNA – the very molecule that defines who we are. It is still fascinating that a molecule that is so small that is not visible to the naked eye determines
not just our physical appearance but also our mental wellbeing. Over 60 years, the discovery of the double helix DNA had impacted various fields
relating to Biology and Chemistry, contributing to the advancement of technology and subsequently mankind too. The discovery ofDNA had opened up
many opportunities in the field of genetics. By analysis a DNA of an individual, we are able to diagnose diseases that are hereditary at an early stage.
Genetic diseases are diseases that arise from one or more abnormalities in a genotype (or genotypes) (Elston, 311). Genetic diseases such as sickle
...show more content...
Paternity tests are done to identify a child's biological parents, which, according to Ian Murnaghan, "has a significant effect on a child's upbringing
and his or her life". Many cases of paternity testing is done to ensure that the biological parent takes responsibility for his or her child. This is not
limited to the entertainment industry, where famous artists such as Mick Jagger were made to take responsibility over his biological son through a
paternity testing (Watson, 286). On the other hand, families are being reunited through the use of DNA as well. Relatives that were separated due to
extreme circumstances were able to reunite with their family. Long lost relatives and children that were given up for adoption had benefitted from this,
allowing them to gain a sense of belonging and a true "home" to return to. Mary–Claire King, who was then a professor of epidemiology and genetics
at the University of California at Berkeley, used genetic testing to reunite children with their grandparents after their parents had "disappeared" during
Argentina's "dirty war" (Kaye, 98).
Apart from humans, DNA had also impacted other living things such as animals and plants. With the discovery of DNA, the agriculture field had
improved tremendously in both quality and quantity. The quest to produce plants that contains better traits had been initiated by Gregor Mendel.
Mendel had worked with the characteristics of pea plants and coined the

Dna And Crime Essay
DNA and Crime
Deoxyribonucleic Acid – the fingerprint of life also know as DNA was first mapped out in the early 1950's by British biophysicist, Francis Harry
Compton Crick and American biochemist James Dewey Watson. They determined the three–dimensional structure of DNA, the substance that passes
on the genetic characteristics from one generation to the next. DNA is found in the chromosomes in the nucleus of a cell.
"Every family line has it's own unique pattern of restriction–enzyme DNA fragments. This variation in patterns of DNA fragments found in
human genetic lineages is called 'restriction–fragment length polymorphism'(RFLP)." (Louis
Levine, ?) Because each person, except for identical...show more content...
The semen matched Kotler's blood and the chances of the semen being somebody else's is one to 7.5 million. Also, dog hairs on the victims clothing
matched hairs from Kotler's German shepherd. Kotler, 37, is free on $25000 bail and could get up to 50 years in jail if convicted of rape and kidnapping.
Anamosa, Iowa: 22 year old Cathy Jo Bohlken was sexually assaulted and murdered. Genetic evidence from fluid taken from her body points to an 18
year old named Travis Jamieson. Bohlkan's body was found DEC 26, 1993 on the floor of her duplex with a bag over her head and her hands wrapped
with duct tape.
Autopsy shows she died of multiple stab wounds. The search of a pick–up truck registered to Jamieson's parents revealed a utility knife and a
"red–brown stain" on the steering wheel. (http://www.wcinet.com/th/news/th0208/stories/1355.htm)
Norman, Okl:Thomas Webb III was released after more than 13 years in prison for a 1982 rape. DNA testing was not available at the time so Gale
Webb, Thomas' wife, pushed authorities to use DNA genetic profiling on the 14 year old evidence. These DNA tests ruled him out as a suspect.
(http://www.wcinet.com/th/news/th0525/stories/12284.htm)
Santa Ana, Calif: Kevin Lee Green cried as the judge apologized for the mistake and freed him from prison after nearly 17 years. He was convicted of
killing his unborn baby and nearly beating his wife to death.
He was released as authorities prepared to charge a

Dna Replication Essay
Since we discovered that DNA is in the nucleus in every single cell, we're curious about how exactly DNA can be replicated in a way that can keep
our identity, including our characteristics. This could be described after learning about DNA and its very individual characteristics, along with
transcription and translation, which are the two steps of DNA replication. These steps can determine our characteristics, as well as our personalities.
DNA is mostly made of adenine, thymine, guanine and cytosine. These all make hydrogen bonds, and that's only if it's connected to the correct base.
An example of this would be when thymine connects to adenine and guanine connects to cytosine. Though, since this is mRNA being created, adenine
would connect...show more content...
The DNA helicase latches on to the DNA molecule, unzipping the double helix, letting enzymes break the hydrogen bonds that connect the base pairs.
Also, complementary nucleotides that are floating around and about in the nucleus form hydrogen bonds according to their pairs: thymine to adenine
and guanine to cytosine. Due to the hydrogen bonds being more breakable, the DNA is much easier to "unzip" for replication. In the cytoplasm you
can also find tRNA. tRNA contains a 3 nucleic code on one side and on the other side, there's a special protein on the other. In the cytoplasm, mRNA
attracts ribosomes that have a similar 3 letter code of tRNA. The amino acids from tRNA then bond with the mRNA, which then creates a protein chain
when a start codon or Methionine is reached. This chain will eventually stop once the stop codon is reached. This will then create a completed protein.
In conclusion, even through replication, we are still able to keep our characteristics due to the stationary and unchanging method of replication, which
is where we keep the same genetic coding. With the steps of DNA replication, this determines our characteristics, along with our personalities. The more
we continue the studying of genetics, we may one day be able to cure disorders before the person is even born or

DNA Essay
DNA
Deoxyribonucleic acid and ribonucleic acid are two chemical substances involved in transmitting genetic information from parent to offspring. It was
known early into the 20th century that chromosomes, the genetic material of cells, contained
DNA. In 1944, Oswald T. Avery, Colin M. MacLeod, and Maclyn McCarty concluded that DNA was the basic genetic component of chromosomes.
Later, RNA would be proven to regulate protein synthesis. (Miller, 139)
DNA is the genetic material found in most viruses and in all cellular organisms.
Some viruses do not have DNA, but contain RNA instead. Depending on the organism, most DNA is found within a singlechromosome like bacteria, or
in several chromosomes like most other living things. (Heath, 110)...show more content...
(Grolier Encyclopedia, 1992)
DNA does not act directly in the process of protein synthesis because it does not leave the nucleus, so a special ribonucleic acid is used as a messenger
(mRNA). The mRNA carries the genetic information from the DNA in the nucleus out to the ribosomes in the cytoplasm during transcription. (Miller,
76)
This leads to the topic of replication. When DNA replicates, the two strands of the double helix separate from one another. While the strands separate,
each nitrogenous base on each strand attracts it's own complement, which as mentioned earlier, attaches with hydrogen bonds. As the bases are bonded
an enzyme called
DNA polymerase combines the phosphate of one nucleotide to the deoxyribose of the opposite nucleotide.
This forms a new polynucleotide chain. The new DNA strand stays attached to the old one through the hydrogen bonds, and together they form a new
DNA double helix molecule. (Heath, 119) (Miller, 144–145)
As mentioned before, DNA molecules are involved in a process called protein synthesis. Without RNA, this process could not be completed. RNA
is the genetic material of some viruses. RNA molecules are like DNA. They have a long chain of macromolecules made up of nucleotides. Each
RNA nucleotide is also made up of three basic parts. There is a sugar called ribose, and at one end of the sugar is the phosphate group, and at the

other end is one of several nitrogenous bases.
There are four main nitrogenous bases found in

Essay On Dna Storage
Hypothetically, if the world we know today was set back to the stone age because of a colossal destruction of a short. Where or how will information
collected by us be preserved? And more importantly how will we binge watch the new season of 'Stranger Things.' Well it's literally inside everyone
and everything, any guesses, it's DNA. So, hypothetically if we're to store information in our DNA does that make us cyborgs, ah? Before we get too
hypothetical, why DNA from all things. First of all, DNA will stand time long before an individual passed and secondly DNA is universal as DNA is
in everyone and everything and thirdly DNA can be easily replicated without a limitation. Therefore, will DNA be the future of storing media? Yes. It's
...show more content...
Then, they sequenced the DNA and successfully decoded the message. It soon became obvious that DNA cryptography could code for much more
than simple text by translating the1's and 0's of binary code into DNA codons." (TED–Ed, 2017) Scientist used DNA codons to code message into
DNA strands and today scientist can code HD movies into DNA codons. To do so scientist used a powerful newgene editing technique (known as
Crispr) to slip the sequence of the DNA molecules that represented the entirety of the film into the genome of a common gut bacteria, named E. coli.
The entire film was preserved and intact (Kolata, 2017).
The limitations of storing DNA is limitless compared to hard–drives as DNA is universal because DNA is found in every organism and can be created
by scratch. This future is closer than ever as mainstream companies such as Microsoft has planned to store their data onto DNA in the next three
years. As the chief scientist of the Semiconductor Research Corporation of Microsoft Victor Zhirnov states. "Is that efforts to shrink computer
memory are hitting physical limits, but DNA can store data at incredible densities. DNA is the densest known storage medium in the universe, just
based on the laws of physics. That is the reason why people are looking into this. And the problem we are solving is the exponential growth of stored
information." (Mcrae, 2017) People in the future will experience the conveniences of storing

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