This document discusses the history and science of DNA. It describes how Dr. Barbara McClintock discovered genetic transposition in corn through her experiments in the late 1920s-1930s. Her discovery of "jumping genes" was initially not widely accepted but was later confirmed. The document also provides an overview of how genetic engineering techniques like restriction enzymes and cloning vectors are used to manipulate DNA and their applications in fields like agriculture and medicine. It concludes with a brief explanation of the structure of DNA and the three main types of RNA.

1. DNA research paper.
Ben Hartman Grant Corrigan Mia Fernandez
A brief history of DNA and a crucial scientist.
DNA is found in every living thing, from humans to microorganisms. Without DNA, we
would all have the same characteristics. The study of DNA was started by a man named
Gregor Mendel, in 1900

2. This discovery was re-discovered by Dr. Barbara McClintock, a geneticist born in 1902.
In the study of genetics, they used ornamental corn to
help them discover how chromosomes carry specific genes to new generations. At
Cornell University in the late 1920’s to early 1930’s, the genetics department brought in
ornamental corn to study. Dr. McClintock started working on identifying and labeling
the 10 chromosomes of the corn. She was able to see the parts of the corn
chromosomes by using new microscopic techniques. She spent many years researching
and finally came to a conclusion much different than the popular belief. She discovered
that genes don’t in fact, stay in one place. They move. She called them “jumping

3. genes”. She believes that these “jumping genes” caused different appearances in
plant’s offspring by either activating or inactivating the gene that controls the color of
the kernels. Dr. McClintock observed two different kinds of transpositions, which are
dissociaters and activators. The dissociaters can “jump” to a different place when
signaled by activators. She concluded that the dissociaters would cause changes and
the nearby genes of the chromosome and the color of the kernels in the ornamental
corn. She verified this conclusion from multiple and repeated experiments. In 1951, Dr.
Barbara McClintock showed her discover to nine groups of scientists from all around the
world at a scientific meeting. Her discovery was not well accepted; the other scientists
were not as amazed as she was and they thought her methods were old fashioned. The
other scientists were using other technologies, such as the electron microscope.
Although her methods were out of date, her discovery was ground-breaking.

4. Her discovery wasn’t really believed
until the 1970s, when a group of molecular biologists found bits of DNA jumping around
in bacteria. Later, scientist found these transpositions in other things besides corn.
They have discovered that every living thing has transpositions. This finally confirmed
that Dr. McClintock’s theory was right all along.

5. The modern manipulation of DNA.
Ever since the discovery of DNA and genes, the manipulation of them has been a
somewhat controversial subject. The technology used in genetic engineering is called
DNA Technology. This technology can be used to cure diseases, to treat genetic
disorders, for the improvement of food crops and much more. Genetic Engineers use
two main parts of the DNA strand to manipulate genes how they want which are called
restriction enzymes and cloning vectors

6. The Restriction Enzymes are used to cut DNA strands into smaller parts which make it
easier for genetic engineers to work with. These restriction enzymes cut the DNA chains
separately between the G nucleotides and the A nucleotides, therefore creating single
chains of DNA. These “tails” are called sticky ends. The sticky ends can bind together
with others so that essentially, two different parts of two different DNA strands can bind
together making an entirely new strand.
After work with restriction enzymes, specific genes can become isolated but cloning
vectors must be used to place the new isolated genes and the new strands previously
combined into an organism. The cloning vector is basically a vessel that is used for the
transportation and cloning from one organism to another. Plasmids, rings of DNA found
in bacteria contain cloning vectors. To use one of these cloning vectors, it has to be
removed from the gene itself. Once the cloning vector is isolated, the plasmid is then
cut, removing the unwanted gene. Once the unwanted gene is removed, the “donor
gene” or the new gene is added.
This remarkable simple process can produce many good things for mankind. It can help
to prevent diseases and in some cases, cure them. Although this process can cause a log
of good and fix many problems, some people believe that this is dangerous and almost
tampering with the fabric of life itself.

7. Before this type of genetic engineering, things were created only by nature, which to
some is ideal. Others feel that genetic engineering is a great milestone for science and
opens up many new possibilities.
Genetic engineering has opened up many possibilities in agriculture and farming alone.
Previously, plants and other types of grown foods were at the mercy of their
environments and the types of infestations or diseases that could hurt them. With
genetic engineering they can make “Franken-foods” that can be resistant to these
forces, where without them they would normally die.

8. How DNA works briefly.
DNA molecules consist of tub long chains each. The chains that DNA is made up of is nucleotides.
Nucleotides are made up of three different parts: those three parts are- sugar molecule, and that is
called deoxyribose. The other is a phosphouris atom and that is surrounded by oxygen atoms; and a
molecule that is referred to as an nitrogen- containing base because it contains a nitrogen atom.
All DNA molecules have an identical sugar base molecule in them that is called deoxyribose sugar
phosphate. Nitrogen molecules contain base, however can be one of four kinds, first is called
adenine (A), second is called guanine (G), third is called cytosine ©, and last is called thymine (T).
The double helix was discovered by James Watson, and Francis Crick in 1953. They suggested that if
they made a model of DNA structure. The model proposed was that DNA is composed of two
nucleotide chains that wrap around each other to form a double spiral. This “double spiral” shape is
now called a Double Helix.
Adenine and guanine combined are called purines. The adenine is made up of NH2, HC, N, NH,
C4, and C. Thymine and cytosine combined are called pyrimidines. Bases just like the two listed
above commonly have two rings of carbon and nitrogen atoms. Such as adenine and guanine are
called purines. Bases that have one ring of carbon and nitrogen atoms such as adenine and guanine
are called pyrimidines.
RNA is like DNA; it is an nucleic acid made up of repeating nucleotides. The difference between
DNA and RNA is that RNA's sugar molecules are ribose, where as DNA's sugar molecules are just
deoxribose sugar. A rare part that is in RNA uracil, that is a nitrogen thymine.

9. There are three different types of RNA, and those three types are called messenger RNA (mRNA),
the second is called transfer RNA (tRNA), and the last one is called ribismoal RNA (rRNA). There
are about 45 variations of (tRNA).