Understanding Elements of DNA

To sum this up DNA is an electronegative molecule with a lacking Oxygen found in the nuclei of Eukaryotes. Now let's go deeper, DNA is not only composed of Sugar, it is also composed of a phosphate backbone, and nitrogenous bases. The phosphate backbone generally expressed as PO4^-3 provides support for the nitrogenous bases [also bonding through ester bonds. The nitrogenous bases in DNA are divided into two Purines [Adenine and Guanine] and Pyrimidines [Thymine, Cytosine, and uracil in RNA] Purines are double ring structures, and Pyrimidines are Single ringed. In other words, they provide the perfect asymmetry of the DNA double helix. When Watson and Crick did their DNA model, they noticed that two Purines bonded together meaning for instance A-G was too wide, and too Pyrimidines bonded together would be too thin. But how did they know which was which? It was found that Adenine always double bonds with hydrogen bonds of course with Thymine, and that Guanine will always triple hydrogen bond with

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 rungs of a ladder, and are joined by alternating phosphate and sugar groups, which may be compared to the ladder 's sides or legs. The bases adenine and thymine form what is known as one base pair, and the bases cytosine and guanine form the second base pair.

In “The Double Helix” by J.D. Watson he tells the story as to how he and Francis Crick discovered the structure of DNA. After reading this book I was able to see how the structure of DNA was discovered since I didn't really have a lot of knowledge as to who discovered DNA besides what the biology book briefly talked about. During this time there was not a lot of people interested in DNA but for the people that were it was almost like a race to see who could discovered it first. Through the book one of their most fierce competition would have to be Maurice Wilkins and Rosalind Franklin. Thanks to their research Watson and Crick were able to discover the structure of DNA first.

DNA is a molecule that converts an organisms genetic blueprint. Every person’s body has the same DNA. Apportion of your DNA is located in the cells nucleus, but a small portion of DNA can also be found in the mitochondria. The DNA structure is very important because it defines who we are and how we look. The information in DNA is stored as a code made up of four chemical bases: adenine, guanine, cytosine, and thymine. The nucleotides are joined to one another in a chain by covalent bonds between the sugar. human DNA have 3 billion bases, and more than 99 percent of those bases are the same as in all the humans in the world. DNA is a nucleic acid; proteins and carbohydrates, nucleic acids compose the three major macromolecules for all known

Erwin Chargaff’s experiments revealed that guanine and cytosine had equal amounts of molecules to each other and that similarly, adenine and thymine had equal amounts to each other. This ultimately suggested to Watson that adenine will always be paired with thymine and that guanine will always be paired with cytosine and that therefore they should fit together in the structure of DNA.

During the 1950’s DNA research was focused on the physical properties, extraction and the contents within differing organisms. At the time the double helix was discovered, 1953, most scientist believe DNA was a conjugated protein. DNA is a nucleic acid, a polymer consisting of many nucleotide monomer and is the blueprint for proteins and cells, which is why they believed it to be a protein. The discovery of the double helix structure and the pairing of the bases to the function of DNA. James Watson and Francis Crick are accredit for the discovery of the double helix as well as the pairing of the bases, adenine with thymine and guanine with cytosine. The pairing advocated that DNA played a role in the copying of genetic material. The theory

DNA is the process of producing two identical replicas from one original DNA molecule. In a cell DNA replication begins at specific locations, or origins of replications, in the genome. DNA usually exists as a double-stranded structure, with both strands coiled together to form the characteristic double-helix. DNA polymerases are a family of enzymes that carry out all forms of DNA replication. DNA polymerases is general cannot initiate synthesis of new strands, but can only extend an existing DNA or RNA strand paired with a template strand. In general, DNA polymerases are highly accurate with an intrinsic error rate of less than one mistake for every 10.7 nucleotides

DNA is the hereditary material and it carries all the genetic information that used in functionally and development of the living organisms. DNA is composed of two DNA strands that are antiparallel, coiled around each other to form a double helix. Double helix stand for two DNA strands set themselves like a ladder with the phosphate backbone forming the side of the ladder and these bases forming the rungs(book). DNA is the polymer of nucleotides, each consisting of three components; nitrogenous base, ribose sugar and a phosphate group. The base can be Thymine(T), Guanine (G), Cytosine(C), Adenine (A); according to the base pairing rule, G=C, T=A. Each strand of the true DNA provides a template for the production of the complementary strand, this is called semi-conservative replication. DNA replication is the technique that produces two identical replicas of DNA from the true DNA molecule and occurs in all living organisms. DNA replication begins within the DNA called origins of DNA replication called ori and when the replication begins,

In the progress of the bases one strand pair can connect with the centers on another strand, e.g. the adenine pairs with thymine, and guanine pairs with cytosine.

B. DNA is located in the nucleus of the cell. Inside each nucleus of a cell is two meters of DNA. The genetic makeup of DNA consists of chemical building blocks of nucleotides. Nucleotides are made up of three bases: phosphate, sugar and nitrogen. The nitrogen bases found in nucleotides are: adenine, thymine, guanine and cytosine. The order of these bases determines what biological instructions are contained in a strand of DNA (Genome.gov, 2014). Adenine pairs with thymine in a two hydrogen bonds while cytosine and guanine pair with three hydrogen bonds (Pray, 2008). The phosphate and sugar bases make up the backbone of the double helix design of a DNA stand. Each backbone contains covalent bonds the hold the structure together. These bonds run anti- parallel forming the sides of the double helix. DNA contains sequences that generate proteins that are called genes. These genes are strings of amino acids that contain instructions for the function of what each

Rosalind Franklin’s work using X-ray diffraction also led to the discovery of the DNA structure for which Watson, Crick and Maurice Wilkins shared Nobel Prize recognition in 1962. (Pray, 2008) Her work included establishing the water content of DNA using X-ray crystallography and fuzzily revealing the pattern of a helical structure with “Photography 51.” (Fredholm, 2017) Franklin was the first person to view DNA, but since she was a woman credit was not granted in her name. She also did not qualify to receive the Nobel Prize as she died 4 years earlier, in April 1958. The Hungarian-born American biochemist Erwin Chargaff contributed in solving the mystery regarding the four nitrogenous bases of DNA. In 1949, he showed that amounts of these bases are always balanced, even if different organisms had different amounts of DNA. This specified a 1:1 ratio of purine to pyrimidine base in each nucleotide and creates a consistent width throughout the DNA molecule. (Fredholm, 2003) Adenine and guanine are larger, double-ringed purines. Thymine and cytosine are smaller pyrimidines. Adenine will only bond with a thymine in DNA; cytosine only to guanine. The complementary bases are paired together with hydrogen bonds. (BiologyWise, 2017) Chargaff’s rules were solidifying insight for Watson to recognize a helix outside of smooth sugar-phosphate backbone and congruent lengths of A-T and C-G bonds in February 1953.

LINK. Replication of DNA is initiated by proteins that recognise a specific sequence of nucleotides from short stretches of DNA at sites called origins of replication. They

The information of DNA is not something that scientists and others have always been aware of. The knowledge in which we hold today is somethings that is a product of multiple studies from multiple people who discovered different aspects of the molecule. Such explanations of explorations of DNA are possible because of the many scientists who paved the way. This began almost a century before the Nobel Prize, in 1868, was awarded to James Watson, Franklin Crick, and Maurice Wilkins. It was a young Swiss physician Friedrich Miescher who located something no one had ever seen before from the nuclei of cells. He named this new found compound “nuclei”. Today we refer to this as nucleic acid, the “NA” in DNA. Gregor Mendel, a Czech monk just two

To understand how DNA is replicated we must first look at how DNA is built. DNA is built in an antiparallel structure, which means that one of the two strands runs from 5’ to 3’, and the other strand runs from 3’ to 5’. Now, we can look at how DNA replication begins. DNA replication begins by unwinding the two DNA strands; an enzyme called helicase accomplishes this. This enzyme uses energy from ATP to unwind the template strand, but like any other process it encounters problems that it must overcome. When DNA is unwound a phenomena called supercoiling can occur—when the DNA is unwound the DNA helix will continue to coil over in space. To overcome this an enzyme called DNA gyrase that helps in relieving the torque that is produced by the unwinding of DNA; this enzyme essentially prevents the helix from supercoiling by changing the topological state of the helix. This enzyme is known as a topoisomerase. To keep the unwound DNA strands from re-biding, a protein called single strand binding protein (SSB) temporarily binds to each template and waits for DNA primase to relieve its position on the strand. DNA primase creates a short RNA sequence on the DNA template strand so that DNA polymerase can make a copy of that DNA strand. This process is one within itself, because it can occur (and does) on either strand (3’ to 5’ or 5’ to 3’) it must lay down primer

The molecular mechanism of the process of replication is directed towards the fidelity of the DNA molecule. Along with numerous interacting enzymes and other molecules working in split second accuracy and timing to synthesize, proof read, repair and eventually produce a newly synthesized strand of DNA with error s at the rate of one per 100 million nucleotides (Alberts et al., 2002). The fundamental process of replication can be considered in three phases-- initiation, elongation and termination.