Genetics relies on chemistry to explain phenomena related to the field. The structure of DNA relies on chemistry. In fact, when James Watson and Francis Crick discovered the structure of DNA, they did so by building models based on the laws of chemistry. Chemistry also relates heavily to the structure and function of one of the main products of DNA: protein. Chemistry dictates the structure of DNA. DNA is a polymer of monomers called nucleic acids. These are made of a nitrogenous base, a phosphate group and a sugar. It is the negative charge on the phosphate group that makes DNA an acid. There are 4 different bases: adenine, thymine, guanine and cytosine. In groups of three, these four bases can code for any protein coded for in an organism’s genome. Two strands of nucleic acids stack on top of each other in a double helix. The backbone of the nucleic acids consists of the interaction between phosphate groups and the hydroxide groups of nucleic acids. These are held together by covalent bonds called phosphodiester bonds. The helix itself is held together by hydrogen bonds. Although h...
The molecule consisted of a double helix with phosphates, deoxyribose sugar molecules, and nitrogenous bases. If the spirals were split, the DNA could replicate, which explained why genes were transferred from parents to their children. Additionally, the order of compounds on the DNA indicated that there was a unique ‘code’ on each strand. Watson and Crick believed that this ‘code’ was translated into specific proteins. , ,
The study of nucleic acids has now become a fruitful and dynamic scientific enterprise. Nucleic acids are of unique importance in biological systems. Genes are made up of deoxyribonucleic acid or DNA, and each gene is a linear segment, or polymer, of a long DNA molecule. A DNA polymer, or DNA oligonucleotide, contains a linear arrangement of subunits called nucleotides. There are four types of nucleotides. Each nucleotide has three components; a phosphate group, a sugar and a base that contains nitrogen within its structure. The sugar moiety in DNA oligonucleotides is always dexoyribose, and there are four alternative bases: adenine (A), thymine (T), guanine (G), and cytosine (C). The phosphate groups and the deoxyribose sugars form the backbone of each DNA stand. The bases are joined to the deoxyribose sugar and stick out to the side. Both oligomers, DNA and RNA, consist of 5’->3’ phosphodiester-linked nucleotide units that are composed of a 2’-deoxy-D-ribose (DNA) or D-ribose (RNA) in their furanose forms and a heteroaromatic nucleobase (A, T, G, and C; A, U, G, C), and the resulting oligonucleotide chain is composed of a polar, negatively charged sugar-phosphate backbone and an array of hydrophobic nucleobases. The amphiphilic nature of these polymers dictates the assembly and maintenance of secondary and tertiary structures the oligonucleotides can form. In the DNA duplex structure, genetic information is stored as a linear nucleotide code. This code can be accessed and replicated. RNA, or ribonucleic acid, is another structurally related essential biopolymer. RNA differs from DNA in having the sugar ribose in place of the deoxyribos...
In April of 1953, James Watson and Francis Crick published a game changing paper. It would blow the mind of the scientific community and reshape the entire landscape of science. DNA, fully knows as Deoxyribonucleic Acid is the molecule that all genes are made of. Though it is a relatively new term with regard to the age of science, the story of DNA and the path to its discovery covers a much broader timeframe and had many more contributors than James Watson and Francis Crick. After reading the paper the audience should have a better understanding of what DNA is, the most important experiments that contributed to its ultimate discovery and the names and contributions of the lesser-known scientists that helped Watson and Crick turn their idea
DNA is composed of three major factors: a five-carbon sugar, a phosphate group, and nitrogenous bases (Biology pg. 259-260). The first major factor is the five-carbon sugar, which is a sugar molecule known as deoxyribose. The second major factor is phosphate group, which acts as a type of backbone and allows the DNA, as well as RNA, the opportunity to form the long chains of nucleotides “by the process of dehydration synthesis (Biology pg. 260).” The third main component is the nitrogenous bases, which can be a purine group, or a two-ringed structure; or a pyrimidine, which is a single-ringed structure.
Deoxyribo Nucleic Acid (DNA) is a chromosome found in the nucleus of a cell, which is a double-stranded helix (similar to a twisted ladder). DNA is made up of four bases called adenine (A), thymine (T), guanine (G), and cytosine (C), that is always based in pairs of A with T and G with C. The four bases of A, C, G, and T were discovered by Phoebus Levene in 1929, which linked it to the string of nucleotide units through phosphate-sugar-base (groups). As mention in Ananya Mandal research paper, Levene thought the chain connection with the bases is repeated in a fix order that make up the DNA molecu...
The first and primary contribution to solving the DNA structure was the relationship of Crick and Watson. Without their teamwork and determination, another scientist would have discovered the structure before them. One of Crick’s bigger contributions was discovering the gene is self-replicating. After talking with John Griffith, Crick came up with the idea that the gene is self-replicating, meaning the gene has the ability “to be exactly copied when the chromosome number doubles during cell division”(126). With further discussion with Griffith, Francis believed that DNA replication involved specific attractive forces between the flat surfaces of the bases (128). One of Watson’s major contributions was after seeing the B form of DNA by Franklin, Watson knew that the structure of DNA was two-chained and that led to the building of the model of DNA (171). Also through research, Watson became aware that adenine and thymine pair together and are held by two hydrogen bonds that were identical in shape to the guanine and cytosine pair held together by at least two hydrogen bonds (194). This discovery showed that the two chains of DNA are complementary to each other. With these individual contributions coming together, Watson and Crick successfully were able to piece together the structure of DNA.
The essential component of life can be acknowledged and is made up of a nucleic acid known as DNA. DNA is the abbreviated form for the word deoxyribonucleic acid and it is the “carrier of genetic information” (McMurry, Ballantine, Hoeger, & Peterson, 1992, pg. 775). DNA contains the genetic instructions that are needed for an organism to develop, survive, and replicate, as it plays a crucial role in living systems that makes each species unique and distinctive. The multifaceted material is stored in every cell of every living organisms and it contains information about our nature, appearance, performance, etc. With the instructions that it contains, DNA is passed from the adult organism to their offspring during reproduction. (McMurry, Ballantine, Hoeger, & Peterson, 1992, pg.777).
Each of the nucleotides accommodate a phosphate group, sugar group, and a nitrogen base. There is four nitrogen bases in DNA. The four nitrogen bases are; Adenine (A), Thymine (T), Guanine (G), and Cytosine (C). Each of the bases are connected to a sugar molecule and a phosphate molecule. They are then positioned into two long strands that form a spiral called a double helix (DNA). The nitrogen bases are paired up with one another. Adenine and Thymine will always be paired with each other because of the bonds between them. Between A and T, there are two hydrogen bonds. The same goes with Guanine always being paired with Cytosine due. Between both G and C there is three hydrogen bonds. The nitrogen bases Adenine and Guanine won’t pair up with each other because, of their size. Both the nitrogen bases Adenine and Guanine are a purine base. Thymine and Cytosine are both a pyrimidine base. Adenine pairs with Thymine, and Guanine pairs with Cytosine, because they are of opposite
Theoretical models for the molecular structure of DNA can be likened to scientific theories. DNA’s structure was determined largely because scientists scrutinized the relationship between theory (a particular theoretical model of DNA) and observation (x-ray crystallographic patterns, or bonding patterns between bases and sugar-phosphate groups, for example). Inductivists, falsificationists, Kuhn, and Feyerabend all have different accounts of how scientists have related theory to observation. These accounts are important because, not only do they delineate frameworks scientists use to develop their theories, but because these frameworks subsequently became important in developing a theory for the molecular structure of DNA.
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.
DNA is the abbreviation for deoxyribonucleic acid. DNA is the genetic material found in cells of all living organisms. Human beings contain approximately one trillion cells (Aronson 9). DNA is a long strand in the shape of a double helix made up of small building blocks (Riley). There are four types of building blocks called bases connected with DNA: adenine, guanine, cytosine, and thymine. Each of the bases is represented by the letters A, G, C, and T. The bases are aligned in a specific order, adenine pairs with thymine and guanine pairs with cytosine; this determines a person’s genetic trait (DNA Initiative).
...d sheet metal to represent the molecule's chainlike structure. They were both very aware that DNA could have had a general, winding shape of a helix, but what still remained a mystery to Watson and Crick was how DNA's four bases (adenine, guanine, thymine, and cytosine) were arranged around a sugar and phosphate backbone.
The main purpose of DNA analysis is to get a visual representation of DNA that is left at the crime scene (Harris, 2013). DNA evidence is an instruction handbook and blueprint for everything in your body (Harris 2013). DNA seems very complex, but it's only made up of four nucleotides, which are Adenine, Cytosine, Guanine, and Thymine (Harris 2013). These nucleotides are base pairs and they join together. Adenine and thymine always join together as a set, and cytosine and guanine join together as a set (Harris 2013). In human cells, DNA is firmly bound into 23 pairs of chro...
DNA, Deoxyribonucleic Acid, is the basic structure for all life, it is the blueprint, the instruction manual, on how to build a living organism. DNA is made up of four nitrogen bases, adenine, thymine, cytosine, and guanine which are connected by sugar-phosphate bonds. Through a process called Protein Synthesis, the nitrogen bases are the code for the creation of amino acids. Essentially, DNA makes amino acids, amino acids make proteins, proteins make organisms. This process has been taking place for much longer than scientists have been able to document. Those scientists are called geneticists and their field is genetics.
By the late 1940s , the people who were in the scientific community were aware that DNA was most likely the molecule of life. The scientific community knew that DNA have four bases which are adenine, thymine, guanine, and cytosine, but one thing they didn't know is what the DNA structure look like. Then come in Sosalind Franklin and Maurice Wilkins, who were using X-ray to find out and understand the physical structure of the DNA molecule. In 1949, Ervin Chargoff, showed that each organisms have different amounts of DNA, but the amount of adeni...