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Chapter 12 the structure of dna
Chapter 12 the structure of dna
Essay on structure of DNA
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Recommended: Chapter 12 the structure of dna
Cancer is a horrible disease that takes thousands of loved ones from their families every year, while millions of dollars are being pumped into cancer research, in hope to find a cure. An area of cancer research that does not get much publicity is epigenetics, which is the study of the heritable changes in DNA that do not affect the DNA sequence itself. Epigenetics plays a significant role in understanding the heritable functions of DNA and how cancer is formed. It is through exploring specific epigenetic changes scientists hope to further understand why these changes occur, and how they affect the DNA.
Basics of DNA:
In order to grasp and visualize how these epigenetic changes occur, a basic understanding of DNA must be achieved. DNA, or deoxyribonucleic acid, is the genetic and hereditary material of almost all living organisms. It is made up of four chemical bases: adenine (A), thymine (T), guanine (G), and cytosine (C) (Hallick). These building blocks, which are sequenced together to make up all the information required for an organism to be built and to function (What is DNA?), think of bases like the letters of the alphabet in how they are specifically ordered to form words, sentences, and entire stories.
Once sequenced, the four bases couple up to form base pairs, with guanine pairing up with cytosine, and thymine with adenine. Each base is attached to a sugar molecule and phosphate molecule to create a nucleotide (Hallick). Nucleotides come together create the commonly seen double helix DNA structure, by being arranged in two long strands which when connected form a spiral (What is DNA?). The double helix structure looks similar to a ladder. The base pairs create the “rungs” of the ladder, and the sugar and phosphate mo...
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Wang, Shaoru, Yuelin Long, Jiaqi Wang, Yushu Ge, Pu Guo, Yi Liu, Tian Tian, and Xiang Zhou. "Systematic Investigations of Different Cytosine Modifications on CpG Dinucleotide Sequences: The Effects on the B-Z Transition." Journal of the American Chemical Society 136 (2014): 56-59. Print.
Temiz, Nuri A., Duncan E. Donohue, Albino Bacolla, Brian T. Luke, and Jack R. Collins. "The Role of Methylation in the Intrinsic Dynamics of B- and Z-DNA." Ed. Claudine Mayer. PLoS ONE 7.4 (2012): 1-9. Print
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Miller, Kenneth R. and Joseph S. Levine. “Chapter 12: DNA and RNA.” Biology. Upper Saddle River: Pearson Education, Inc., 2002. Print.
Histone modification may or may not be dependent on DNA methylation and is difficult to detect compared to LOH.
Hall, Linley Erin. “Understanding Genetics DNA and RNA.” New York: The Rosen Publishing Group, Inc., 2011. Print. 01 Apr. 2014.
DNA methylation primarily occurs within sites in the DNA sequence known as CpG dinucleotides, which is a 2 base pair sequence involving a Cytosine bonded to a Guanine by a phosphodiester bond.
Epigenetics is the word that is used for genes that are modified in order to assist certain genome sequences that lead to diseases and disorders. Epigenetics has come a long way since the first genome sequence had its draft breakthrough in the year 2000 (NOVA 2012). From depression to cancer, epigenetics has made its way through to provide families with the appropriate knowledge and perhaps medication in order to avoid these diseases and disorders in the future.
Tsou, J. A., Hagen, J. A., Carpenter, C. L., & Laird-Offringa, I. A. (2002, August 05). DNA
The cancer cells from gene-mutation. Scientists now know some of the risk factors for lung cancer can cause certain changes in the DNA of lung cells. These changes can lead to not normal cell growth and, sometimes, cancer. DNA is the chemical in each of our cells that makes up our genes and how our cells function. People usually look like their parents because they are the source of our DNA. But DNA affects more than how we look; it also can affect our risk for developing certain diseases, including some kinds of cancer like lung cancer etc…Some people inherit DNA mutation from their parents that greatly increase their risk for developing certain cancers.
A chromosome is made up of two identical structures called chromatids. The process of nuclear division is called interphase; each DNA molecule in a nucleus makes an identical copy of itself. Each copy is contained in the chromatid and a characteristic narrow region called the centromere holds the two chromatids together. The centromere can be found anywhere along a chromosome but the position is the characteristic for a particular chromosome. Each Chromatid contains one DNA molecule. DNA is the molecule of inheritance and is made up of a series of genes. The fact that the two DNA molecules in the sister chromatids, and hence their genes, are identical is the key to precise nuclear division.
As previously stated, there are several ways that these changes can occur, but the ones I will be focusing on are changes occurring to methyl and acetyl groups. The mechanism of heritability in animals is information coded into genes. Genes are wrapped around histones in the nucleus. When methyl groups attach to these histones, it winds the genes tighter, and since the shape is altered, it also alters the protein the gene codes for. Generally speaking, when you add a methyl group onto the histones, or "spool" of the gene, it makes it harder to code that gene’s proteins, just like if you got something stuck in the chain on your bike and tried to pedal it. The more methyl groups that build up, the worse the problem becomes. However, in most of the cases acetylation unwinds some of the histones, activating or reactivating a gene. Scientists are explo...
The American Cancer Society publishes current advances made in cancer research on their website. Many of the exciting discoveries about how best to treat the disease focus on the genetic aspects associated with certain types of cancer. In addition, treatments aimed at genetic solutions to cancer may be more effective and may cause fewer adverse side effects than traditional cancer treatments (American Can...
Cancer develops when cells in a part of the body begin to grow out of
Cancer is a disease that affects human somatic cells. It causes the cells to divide uncontrollably and form masses known as tumors. There are two different types of cancer tumors. Some tumors are benign and other tumors are malignant. Benign tumors look similar to the tissues that they came from and develop slowly. The tumor remains in the same area that the tumor originated in. Malignant tumors are formed from cells that do not resemble the tissue that they came from. They vary in shape and size. This enables pieces of the tumor to break off and spread to other places in the body. Over the past few decades cancer has become a very prominent disease. There are many different types of cancer and many different causes for the the disease. Most cancers are because of a genetic mutation. The most common type occur when a cell is dividing. Proto-oncogenes, which are alleles in a normal cells, mutate to form oncogenes. These oncogenes cause cancer because they do not allow the cells to self destruct or become epistatic. There have been several research projects which have been testing epistatis.
Inside the cells that produce sperm and eggs, chromosomes become paired. While they are pressed together, the chromosomes may break, and each may swap a portion of its genetic material for the matching portion from its mate. This form of recombination is called crossing-over. When the chromosomes glue themselves back together and separate, each has picked up new genetic material from the other. The constellation of physical characteristics it determines is now different than before crossing-over.
A recent field of biology, called epigenetics, is rapidly transforming previous ideas on the impact of genes. The...
DNA (deoxyribonucleic acid) is a self-replicating molecule or material present in nearly all living organisms as the main constituent in chromosomes. It encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses. Simply put, DNA contains the instructions needed for an organism to develop, survive and reproduce. The discovery and use of DNA has seen many changes and made great progress over many years. James Watson was a pioneer molecular biologist who is credited, along with Francis Crick and Maurice Wilkins, with discovering the double helix structure of the DNA molecule. The three won the Nobel Prize in Medicine in 1962 for their work (Bagley, 2013). Scientist use the term “double helix” to describe DNA’s winding, two-stranded chemical structure. This shape looks much like a twisted ladder and gives the DNA the power to pass along biological instructions with great precision.