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 forensics is a division of forensic science that focuses on the use of genetic material in criminal investigation to answer questions pertaining to legal situations, including criminal and civil cases. Through DNA testing, law enforcement officers are able to identify human remains or the individual responsible for a crime. DNA testing is a highly advanced scientific process that involves replicating the human DNA sequence to create a genetic map of an individual. Because of its reliability, DNA testing has become a significant factor in criminal cases. However, it has also been identified as having the potential to violate privacy and constitutional rights. The DNA identification process consists of five stages. These five stages
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.
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.
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.
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.
Each human being has something called DNA. DNA is described as genetics and an extremely long macromolecule that is the main component of chromosomes and is the material that transfers genetic characteristics in all life forms. DNA constructs of two nucleotide strands coiled around each other in a ladder like arrangement with the sidepieces composed of alternating phosphate and deoxyribose units and the rungs composed of the purine and pyrimidine bases adenine, guanine, cytosine, and thymine. Each chromosome consist of one continuous thread-like molecule of DNA coiled tightly around proteins and contains a portion of the 6,400,000,000 basepairs that make up your DNA.
DNA is a term that has been used in science as well as in many parts of daily
Strands of the DNA are composed of a sugar and phosphate, portions of the nucleotides while the middle parts of the DNA are made up of nitrogenous bases. The hydrogen bonds between phosphates cause the DNA strand to twist. The nitrogenous bases point inward on the ladder and form pairs with bases on the other side, like rungs. The nitrogenous bases on the two strands of DNA pair up, purine with pyrimidine (adenine with thymine and guanine with cytosine) and are held together by hydrogen bonds. DNA has a spiral staircase-like structure. The steps are formed by the nitrogen bases of the nucleotides where adenine pairs with thymine and cytosine with
There are several enzymes that take part in the DNA replication process. They are Helicase, DNA Polymerase III and Primase. In helicase, this enzyme has several functions in helping make the replication fork so different functions are allowed to occur (Wolfe, 2016). Helicase unravels the double DNA helix to a single stranded template of Adenine, Thymine, Cytosine and Guanine allowing these to be copied (Wolfe, 2016). DNA helicase during single strand separation from the helix also forms the replication fork (Wolfe, 2016). This in turns during the single strand of the nucleotides A, T, C, G still have match together for correct sequence
Allowing the annual report of the National DNA Database Strategy Board as of 2012-2013, NDNAD helps the law enforcement in giving worthful information that will lead in determining the suspect and solve crime cases. However, sometimes the crime doesn’t solve and more evidence needs to be collecting to secure a conviction but in dealing with NDNAD it provides the police of its needed information for DNA matches.
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
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.
Deoxyribonucleic (DNA) is the molecule that hold the genetic information of living things. In our body every cell contains about 2 meters of DNA. DNA is copied every time a cell divides. Deoxyribonucleic (DNA) is made up of two polynucleotide strands. Polynucleotide strands twist around each other, forming a shape that looks like a ladder called a double helix. The two polynucleotide strands run antiaparallel to each other with nitrogenous bases this means that the stands run in opposite directions, parallel to one another. The DNA molecule consists of two backbones chains of sugars and phosphate groups. The organic bases held together by hydrogen bonds. Although bases bonded together are termed paired
The process of DNA replication plays a crucial role in providing genetic continuity from one generation to the next. Knowledge of the structure of DNA began with the discovery of nucleic acids in 1869. In 1952, an accurate model of the DNA molecule was presented, thanks to the work of Rosalind Franklin, James Watson, and Francis Crick. To reproduce, a cell must copy and transmit its genetic information (DNA) to all of its progeny. To do so, DNA replicates following the process of semi-conservative replication. Two strands of DNA are obtained from one, having produced two daughter molecules that are identical to one another and to the parent molecule. This essay reviews the three stages