Essay About Dna

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
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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,

DNA and Crime Investigation Essay
DNA is deoxyribonucleic acid, which is found in almost all living things. DNA serves as a code for
the creation and maintenance of new cells within an organism. Within humans, it is found in almost
every cell. Although most of our DNA is found within the nucleus of our cells as nuclear DNA, a
very small amount of our DNA is also found within the mitochondria as mitochondrial DNA.
Because mitochondrial DNA is generally not used for solving crimes, for the purpose of this paper it
will be disregarded.
DNA is a long curved structure, made up of pairs of four specific bases: adenine, guanine, cytosine,
and thymine, is the repository of a code from which all of our cells are made. The code is made up
of base pairs which look like the...show more content...
Although DNA was initially observed by Frederich Miescher, a German biochemist near the end of
the nineteenth century, the key to the structure of DNA was not discovered until almost a hundred
years later. It was at that time that science realized the importance of DNA to the study of biology.
In 1953 four scientists: James Watson, Francis Crick, Maurice Wilkins and Rosalind Franklin
completed a DNA model which they created using observed X–ray diffraction patterns. This model
showed how the structure of DNA was able to transmit genetic information from parents to their
offspring.
The work of these four people led to a complete restructuring of the beliefs of the scientific
community regarding genetic information. Their initial word led to further work which
encompassed their hypothesis of how DNA replicates itself. From this work came the modern
technologies of DNA fingerprinting and sequencing.
DNA fingerprinting is a technique that is used to determine how likely it is whether genetic
material came from a specific person or family group. Since 99% of human DNA is identical, that
means that it is only 1% of our DNA which is different, and it is that 1% that we look at when we
are attempting to determine the origin of a DNA sample.
Enzymes are applied to DNA to break it into smaller pieces which are called restriction
endonucleases. These restriction endonucleases become

The Molecular Structure Of Dna
"Deoxyribonucleic acid, or DNA is the molecule that transports most genetic instructions utilized in
the growth, function and biological process of all living organisms and many viruses."
(Merriam–Webster Dictionary) It was first discovered at the University of TГјbingen by Friedrich
Miescher in 1869. Miescher discovered DNA through a microscopic substrate in a sample of pus on
unwanted surgical gauze. (Dahm)
Nature is a scientific journal in Britain, where studies and academic research in scientific fields are
published. In 1953, Francis Crick and James D. Watson published a scientific article describing the
molecular structure of DNA. They also described the detection a double–helix, using scientific data
collected by Rosalind Franklin and Maurice Wilkins. With the use of X–ray diffraction and
mathematics of a helix transform, Crick and Watson were able to figure out the DNA's structure.
(Nature 171)
The structure of DNA is the double–helix discovered by Watson and Crick. The discovery of this
made it possible to understand that genes are the defined parts of DNA molecules. The building
blocks paired specifically with each other and are called nucleotides. Nucleotides are organic
molecules that help as monomers of nucleic acids like DNA. They also help carry energy inside the
cell. (Watson JD, Crick FH)
Guanine, cytosine, adenine, and thymine are the nucleobases found in the DNA. The guanine
amount is the same as cytosine and the amount of adenine is the same for thymine.

Genomics Essay
Genomics
Genomics is the study of the functions of genes and DNA in an organism, including location,
structure, sequence, regulation and function. The genome provides a list of building materials for
proteins. (Kerns/McDonald, 2001) Today scientists are striving to identify every gene in human
DNA and the sequences of the chemical base pairs that make up each one. This is noeasy task, but
within the next few years, the world will acknowledge genomics as the biggest thing since sliced
bread. Scientists intend to store the data in databases, develop new sequencing technologies, and
develop tools for data analysis. Both Celera and the Human Genome Project completed rough drafts
of the Genome Project in June...show more content...
(Bird, 2000)
Such therapeutic products will also be invaluable for individuals to identify the types of genes their
children will express before they are born. Each individual's medical record will include the
complete genome as well as single base–pair variations that will be able to predict responses to
drugs and environmental substances. (Drell/Adamson, 2001) Through genetic research, doctors
will be able to alter the mutation of a bad set of genes, and cure a diseased embryo before it is
born. Since a hereditary disorder is the result of one defective gene, gene therapy will enable
scientists to add a working copy of that gene. This procedure will result in a cure for hereditary
diseases such as cystic fibrosis and muscular dystrophy. (Raven/Johnson, 2002) With the knowledge
of one's genome, an individual can alter his lifestyle to reduce the likelihood of developing such
hereditary diseases. (Drell/Adamson, 2001)
Other areas of genetic research for hereditary diseases include cancer, cardiovascular diseases,
metabolic disorders, neurological disorders, respiratory disorders, and infectious diseases. Scientists
will be able to correct the over–expression of p53 genes, which, if copied too many times, may lead
to cancer. When scientists are able to correct the loss of the p53 tumor suppressor gene, they will
stop the spread of cancer. Scientists will gain a deeper understanding of drug metabolism and the

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 with complaints 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

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 of
DNA 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 And Sequence Of Dna Essay
DNA (deoxyribonucleic acid) is a self–replicating nucleic acid that carries the genetic information in
cells in a double helix structure. The 2 stranded helix is composed of 4 nucleotides, Adenine (A),
Thymine (T), Guanine (G), and Cytosine (C). The base pairs only form between A and T
connected by 2 Hydrogen bonds and G and C connected by 3 hydrogen bonds. Foremost DNA
wrapping comes about as DNA wraps around protein called histones. These combined loops of
DNA and protein are called nucleosomes and the nucleosomes are packaged into a thread called
chromatin. Chromosomes are made up of packaged chromatin and can be seen in the nucleus of
dividing cells and form around DNA replication. Furthermore, DNA replication begins with 2 DNA
strands being separated by the helicase enzyme. Single stranded DNA binding proteins attach to
these strands to keep them from re–connecting. 1 DNA strand begins to encode called the leading
strand, which Forms from 5' to 3' end using DNA polymerase 3 the primary polymerase. The
other strand is referred to as the lagging strand, which presents problems because it has to form
from the 5' to 3'end as well. As continuous replication of the leading strand continues the lagging
strand forms in pieces called Okazaki fragments. RNA primase forms as RNA primer and
polymerase III lay down new DNA. This process repeats again and again. DNA polymerase I
replaces RNA primers with DNA and DNA ligase links the Okazaki fragments. Along with the
process of DNA

DNA EXTRACTION Essay
Much can be learned from studying an organisms DNA. The first step to doing this is extracting
DNA from cells. In this experiment, you will isolate DNA from the cells of fruit. Materials (1) 10
mL Graduated Cylinder(2) 100 mL Beakers15 cm Cheesecloth1 Resealable Bag1 Rubber Band
(Large. Contains latex pleasewear gloves when handling if you have a latex allergy).Standing Test
TubeWooden Stir StickFresh, Soft Fruit (e.g., Grapes, Strawberries, Banana, etc.) ScissorsDNA
Extraction SolutionIce Cold EthanolYou Must ProvideContains sodium chloride, detergent and
waterFor ice cold ethanol, store in the freezer 60 minutes before use. Procedure If you have not
done so, prepare the ethanol by placing it in a freezer for approximately 60 minutes....show more
content...
Let the test tube sit undisturbed for 2 – 5 minutes. You should begin to see air bubbles form at the
boundary line between the ethanol and the filtered fruit solution. Bubbles will form near the top, and
you will eventually see the DNA float to the top of the ethanol. Gently insert the stir stick into the
test tube. Slowly raise and lower the tip several times to spool and collect the DNA. If there is an
insufficient amount of DNA available, it may not float to the top of the solution in a form that can
be easily spooled or removed from the tube. However, the DNA will still be visible as white/clear
clusters by gently stirring the solution and pushing the clusters around the top. Post–Lab Questions
What is the texture and consistency of the DNA DNA is viscous and greasy. Why did we use a
salt in the extraction solution High salt makes DNA less soluble in water. In order to dissolve, the
water needs to interact with the DNA. Since DNA is quite large, it needs to interact with lots of
water for this purpose. When you add salt, the water preferentially interacts with the salt (its small,
and can move around in solution easier than the DNA can). This makes it so there is less water
available to interact with the DNA and it becomes less soluble. Is the DNA soluble in the aqueous
solution or alcohol DNA is less soluble in an alcohol such as isopropanol than it is in water. This is
because alcohols are non–polar, whereas water is polar. The polar

Essay about DNA: The Basis for Sustaining Life
History of DNA
Have you ever asked yourself "why my eyes are this color?" Have you questioned why you look
the way you do? All of your physical features come from our genetics. Those genetics are family
traits that are passed down through our individual bloodline. All of these individualities come from
what is considered the fundamental building blocks of life, DNA.
DeoxyriboNucleic Acid is the scientific name for DNA (SITE). A Swiss medical student named
Johann Friedrich Miescher discovered DNA in 1868 (SITE). Miescher was investigating the white
blood cells of pus from a surgical wound. It was there in these white blood cells that he found the
"hot to manual" that defines what we look like. It is important to note, DNA is in...show more
content...
Individual DNA is created at the moment of conception and never changes throughout our lives.
During conception a chemical known as nucleic acid is created and duplicates and divides itself an
infinite number of times. Even through repetitive replication and division, the DNA is always an
exact copy of the first DNA strand.
Conception also joins the father's sperm with the mother's egg creating a genetic sequence (23
chromosomes from your father and 23 from your mother) of the 46 chromosomes. It is these 46
chromosomes that make up the complete instructional guide for who we are. Half of the
chromosomes come from each parent, allowing for all the variations in our offspring.
Scientists have said the human genome is comprised of "approximately three billion DNA
molecules" (Simon & Dickey, 2012). In general, we are made up of about 30,000 different genes that
are spread between 46 chromosomes. With so many different chromosomes, there are an infinite
number of variations that two parents can make–up. Also, the DNA of each person details a variety
of information to include how long you are likely to live.
All of the chromosomes that make up our DNA are coiled up inside the nucleus of eukaryotic
cells. Aside from the reproductive cells, each and every cell contains the 46 linear chromosomes.
Of those 46, there are 23 pairs of chromosomes. Of those 23, 22 are similar in size, shape and even
genetic content. The 23rd

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.

How DNA Helps to Solve Crimes Essay
Deoxyribonucleic acid (DNA) has been used to analyze and prove innocence or guilt of suspects
of crimes with great accuracy. DNA is part of everyday life. It is the heredity material in humans
and almost all other organisms. While being part of an investigation. DNA has helped to solve
crimes. There is a couple ways that DNA left behind can be tested to solve a crime. Either if the
suspect has been caught and or had his or her DNA tested, or if he or she has left behind any
biological evidence. Which then needs to be tested to see if it matches the DNA found in the crime
scene to his or hers DNA. The result to this comparison may help establish if the suspect committed
the crime. Although the chemical structure in everyone's DNA is the...show more content...
This process is called DNA finger printing. Therefore, DNA is one of the most common things a
forensic technician looks for. Forensic technicians investigate crimes. There job is to look for
physical evidence that will be collected and later analyzed. While working on an investigation
the forensic technician may seem to be looking for a specific sample. It may be a blood sample
or even a single drop of saliva. In some cases, clues may lead to a single fingerprint left behind to
solving a crime. The suspect assuming he or she has wiped away all traces that would lead them
to the crime scene. Never realizing what the suspect might have left behind. This may have
seemed irrelevant to the forensic technician. Who is taking part in searching the crime scene.
DNA left behind such as a strand of hair leads to a suspect. To the result it may be found in the
carpet, or in any other type of clothing. Even though DNA evidence is generally linked to an
offenders profile through DNA database. In the late 1980's the federal government laid a ground
work for the system of state, local and national DNA databases for the storage and exchange of
the DNA profiles. This system was named the Combined DNA Index System (CODIS).
Maintaining DNA profiles set of databases that can be shared to the law enforcements all across the
country. The CODIS can compare crime scene evidence that has been stored to a database of DNA
profiles obtaining previous offenders. This

Use of DNA in Criminal Investigations Essay
Before the 1980s, courts relied on testimony and eyewitness accounts as a main source of evidence.
Notoriously unreliable, these techniques have since faded away to the stunning reliability of DNA
forensics. In 1984, British geneticist Alec Jeffreys of the University of Leicester discovered an
interesting new marker in the human genome. Most DNA information is the same in every human,
but the junk code between genes is unique to every person. Junk DNA used for investigative
purposes can be found in blood, saliva, perspiration, sexual fluid, skin tissue, bone marrow, dental
pulp, and hair follicles (Butler, 2011). By analyzing this junk code, Jeffreys found certain sequences
of 10 to 100 base pairs repeated multiple times. These tandem...show more content...
DNA forensics can also narrow down suspect pools, exonerate innocent suspects, and link crimes
together if the same DNA is found at both scenes. However, without existing suspects, a DNA profile
cannot direct an investigation because current knowledge of genotype–phenotype relation is too
vague for DNA phenotyping. For example, a profile from a first time offender that has no match
in any database may give the information that the criminal is a left handed male of medium stature
with red hair and freckles. It would be impossible to interview every man who fits that description.
However, with available suspects, DNA forensics has many advantages over other forms of
evidence. One is the longevity of DNA. Although it will deteriorate if exposed to sunlight, it can
remain intact for centuries under proper conditions (Sachs, 2004). Because DNA is so durable,
investigators can reopen old cases to reexamine evidence.
DNA from animals and plants can also be utilized in criminal forensics. One of the most common
applications of this is the analysis of pet hair from a crime scene, which often links its owner to the
crime. DNA fingerprints have also been applied to cannabis plants, and a database is being created
to trace samples to their sources. This has been extremely successful so far, as this technology can
distinguish between closely related, carefully bred plants (Westphal, 2003). Heather Miller Coyle of
the Connecticut

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 of DNA 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 Gene Essay
The topic i chose was DNA and the gene, because I think that it's cool how these little particles can
make such a big difference in our bodies either in a positive or negative way. Behind talking about
the DNA and gene I'm also including the things that can happen if anyone of these were not to
function normally. The diseases i choose to talk about is the Huntington disease, sickle cell, genetic
disease, Down syndrome, cancer, and genetic disorder. DNA and gene play a major role in these
diseases because they determine what your body does and what it does not do.
The DNA is a self–replicating material that is in almost all living organisms as the main constituent
of chromosomes. DNA is short for deoxyribonucleic...show more content...
Later then, the chromosomes are organized again into smaller pieces of DNA called genes. That's
what connects the chromosome with the DNA and the gene. The DNA bases tell the cells how to
function and what traits they will express. A chromosome is a thread like structure including the
nucleic acids and protein
which is found inside the nucleus of most living cells carrying genetic information in form of the
gene. The structure of the chromosome is sort of like an X structure. The middle of the X is called
the centromere and divides into 2 sections or arms. The short arm of the chromosome is labeled as
the "palm", the longer arm is labeled as the "q arm". It's made up of DNA tightly colliding together
many times around proteins called histones and that's what supports the structure. There are 20,000 –
25,000 protein coding genes on every single chromosome, humans normally have 46 chromosomes
in each cell that are divided into 23 pairs. There are 2 copies of chromosome 8, one copy gets
inherited from each of the parents to form one of the pairs.
The few diseases that DNA and the gene cause are cancer, sickle cell anemia, genetic disease,
Huntington disease, and genetic disorder. The first one I'm going to talk about is cancer. Cancer is
a genetic disease caused when there is a change in genes that causes our cells to function

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 single chromosome 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 thebases 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 Discoveries
Discoveries in DNA, cell biology, evolution, biotechnology have been among the major
achievements in biology over the past 200 years with accelerated discoveries and insights over the
last 50 years. Consider the progress we have made in these areas of human knowledge. Present at
least three of the discoveries you find to be most important and describe their significance to society,
health, and the culture of modern life.
DNA per medical dictionary is defined as A nucleic acid that carries the genetic information in cells
and some viruses, consisting of two long chains of nucleotides twisted into a double helix and joined
by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine.
DNA sequences are...show more content...
Thus, proteins that are formed play certain roles as the body synthesizes those specific proteins for
the exact job at the exact time. Some of the diseases affected by this are sickle cell and malaria.
Sickle cell: One of the first inherited diseases to be unraveled at the level of DNA was sickle–cell
anemia which is defined as abnormal, crescent–shaped red blood cells that results from a single
change in the amino acid sequence of the cell's hemoglobin, which causes the cell to contort,
especially under low–oxygen conditions. (medical dictionary, 2017) Also, called drepanocyte,
meniscocyte. Also, this blood disorder mostly affects Africans and natives of the Mediterranean
region are those who are affected by malaria. A single mutation in thegene for the blood protein
hemoglobin can affect its ability to transport oxygen around the body. People who inherit two copies
of the same mutation, one from each parent, have severe symptoms.
Malaria: However, those who inherit just one copy of the mutation do not suffer too badly; in fact,
they are resistant to malaria which defined as an infective disease caused by sporozoan parasites that
are transmitted through the bite of an infected Anopheles mosquito; marked by paroxysms of chills
and fever. The discovery told geneticists much about evolution and how harmful mutations can
increase to relatively high levels within a population provided they confer some advantage. By
understanding how

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 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

Essay about Dna in Criminal Investigation
Since its discovery in the 1980's, the application of DNA has been utilized in many ways. When
Deoxyribonucleic Acid, or DNA is examined, a precise decoding of genetic information is
revealed. With the exception of identical twins, every person's genetic code (commonly referred to
as a Genetic Fingerprint) is inherited and unique. From Maury advising men everyday on TV "You
ARE the Father!" or "You are NOT the Father!" to learning the descendents of former slaves are
related to President Thomas Jefferson, we have come to rely upon and expect the accuracy of DNA.
DNA almost immediately transformed the American Criminal Justice System. Law Enforcement,
District Attorneys, Defense Attorneys, Criminal Court and Family Court all work...show more
content...
The rape victims told police their attacker was about 160 pounds; Anthony Capozzi weighed over
200 pounds. Capozzi has a prominent three inch scar on his face, but none of the rape victims
reported their attacker had a scar. Despite this all three victims identified Anthony Capozzi as the
man who raped them. His case went to trial and he was convicted of two of the three rapes and
sentenced to 35 years in prison. The only identification evidence introduced at trial was that of the
victims. After he was convicted, Capozzi's attorney is quoted in the Washington Post as saying,
"Please don't take comfort in the fact that Anthony Capozzi has been convicted of these two
crimes, because he didn't do them. Don't feel that you can go running without company in
Delaware Park." Capozzi struggled with mental illness and served 15 years of his prison sentence
in Central New York Psychiatric Center. Capozzi maintained his innocence, and for the 22 years
while he was incarcerated his family never gave up hope. After Capozzi was incarcerated the
rapes continued, and the Bike Path Rapist became the Bike Path Killer. In addition to a
continuing series of rapes in the area, two University of Buffalo students and the wife of a
University of Buffalo professor were all murdered. A combination of old fashioned detective work
and the science of DNA helped to solve a case that has spanned over two decades and involved over
twenty five victims. On

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