Structure and function of nucleic acids flashcards quizlet. Thus, nucleic acids are macromolecules of the utmost biological importance. Nucleotides are composed of a fivecarbon sugar covalently attached to a phosphate group and a base containing nitrogen atoms. In this section, we will examine the structures of dna and rna, and how these structures are related to the functions these molecules perform. These large molecules are called nucleic acids because they were first identified inside the nucleus of cells, however, they are also found in mitochondria and chloroplasts as well as bacteria and viruses. This article provides an overview of nucleic acid structure, as. Nucleic acid formation from nucleotides the assembly of nucleotides into polynucleotides, or nucleic acids, can be thought of as a dehydration reaction between the 3oh of one nucleotide and the phosphate group of a second nucleotide to form a phosphodiester bond. Dna also known as deoxyribonucleic acid is the most important biological molecule present in living cells. These molecules are composed of long strands of nucleotides. The nucleic acids, dna and rna, may be thought of as the information molecules of the cell. For nucleic acids, tertiary structure refers to the overall threedimensional shape.
The structure of a polynucleotide is shown diagrammatically above. The key concept is that some form of nucleic acid is the genetic material, and these encode the macromolecules that function in the cell. The two nucleic acids differ in their structure, function, properties, and location within the cell. Dna stores genetic information used for the synthesis of proteins including enzymes and is found in the nucleus and mitochondria. Protein composition and structure biology libretexts. The linear sequence of amino acid residues in a polypeptide chain determines the threedimensional configuration of a protein, and the structure of a protein determines its function.
Nucleic acids are macromolecules that store genetic information and enable protein production. Sep 17, 2014 this video lecture discusses the structure and function of nucleic acids. The primary function of nucleic acids, which in nature include dna and rna, is to store and transfer genetic information. A number of other nitrogenous bases have been identified in dna and rna, but these occur much less frequently. Nucleic acids principles of biology from nature education. Pdf an overview of nucleic acid chemistry, structure, and function. He wanted to determine the chemical composition of leucocytes white. The repeating, or monomer, units that are linked together to form nucleic acids are known as nucleotides. The recommendations presented here are designed to support easier com munication of nmr data and nmr structures of proteins and nucleic acids through unified nomenclature and reporting standards. There are a very few different types of nucleotides. Molecular structure of nucleic acids a structure for deoxyribose nucleic acid we wish to suggest a structure for the salt of deoxyribose nucleic acid d.
The main function of the nucleic acids is to transmit genetic material or information from parent cell to the daughter cells or from one generation to the next. Nucleic acids are polymers composed of monomer units known as nucleotides. We wish to put forward a radically different structure for the salt of deoxyribose nucleic acid. The rapid developments in the area of genetic engineering and recombinant dna. Nucleic acid nucleic acid deoxyribonucleic acid dna. Start studying structure and function of nucleic acids. Their main function is to maintain and transmit the genetic code.
Dna is the genetic material found in living organisms, all the way from singlecelled bacteria to multicellular mammals like you and me. Lipids 25 o fatty acids o hormones derived from fatty acids. Structure and function of biomolecules 8 structure and function of biomolecules table of contents 1. Because a nucleic acid is a polymer of many nucleotide molecules, dna and rna molecules are called polynucleotides. This biochemistry video tutorial provides a basic introduction into nucleic acids such as dna and rna. Among these building blocks were nucleic acids, longchain polymers. Nucleic acids were named based partly on their chemical properties and partly on the observation that they represent a major constituent of the cell nucleus. We will discuss these nucleic acids in detail in this section. The structure and function of nucleic acids revised edition. Pdf chemists and early biochemists determined the essential building blocks of living cells and characterized their chemical nature.
Nucleic acids are large molecules where genetic information is stored. Objectives by the end of lecture the student should. Nucleic acid structure refers to the structure of nucleic acids such as dna and rna. The biochemistry of the nucleic acids article pdf available in the yale journal of biology and medicine 422 september 1969 with 1,636 reads how we measure reads. They control the important biosynthetic activities of the cell and carry hereditary information from generation to generation. Nucleic acids can be found within the nucleus and cytoplasm of our cells. Dna is metabolically and chemically more stable than rna. Nucleic acids consist of nucleotides, which in turn are composed of a sugar, a phosphate group and a nitrogenous base. These nitrogencontaining bases occur in complementary pairs as determined by their ability to form hydrogen bonds between them. They both carry genetic information, but their roles are vastly different. Mar 06, 2015 nucleic acids were first isolated from the cellular nucleus, hence the name.
They are necessary for growth and transmission of impulses in the nervous system. Secondary structure refers to the shape of a folding protein due exclusively to hydrogen bonding between its backbone amide and carbonyl groups. Chapter 2 structure and function of nucleic acid chapter 2 structure and function of nucleic acid contents composition of nucleic acids structure and function of dna. In dna, tertiary structure arises from supercoiling, which involves double helices being twisted into tighter, more compact shapes. Sep 25, 2016 a nitrogenous base is connected to the carbon atom no. They are composed of nucleotides, which are the monomers made of three components. There are two types of nucleic acids, deoxyribonucleic acid, dna, and ribonucleic acid, rna. This information is stored in the form of long polymer chains. Nucleic acid structure depends on the sequence of bases andon the type of ribose sugar ribose, or 2deoxyribose. The bform of dna has a prominent major groove and a minor groove tracing the path of the helix figure 2. Although the information they carry is onedimensional, it is essential to understand the 3d structure of nucleic. Hydrogen bonds between the base pairs hold a nucleic acid duplex together, with two hydrogen bonds per at pair or per au pair in rna and three hydrogen bonds per gc pair. Nucleic acid, naturally occurring chemical compound that is capable of being broken down to yield phosphoric acid, sugars, and a mixture of organic bases purines and pyrimidines.
Nucleic acid function and basics the function of dna and rna is to store genetic information. This structure as described is rather illdefined, and for this reason we shall not comment on it. Function of nucleic acids the purpose of dna is to act as a code or recipe for making proteins. Prior to that time, there was considerable disagreement. Jan 25, 2020 two examples of nucleic acids include deoxyribonucleic acid better known as dna and ribonucleic acid better known as rna. The composition of the desoxypentose nucleic acids of thymus and spleen. A and g are categorized as purines, and c, t, and u are collectively called read more. He found a weakly acidic substance of unknown function in the nuclei of human white blood cells and named it nuclein. Nucleic acid history nucleic acid history nucleic acid structure more on nucleic acids rna protein synthesis more protein. Structure of nucleic acids molecular cell biology ncbi bookshelf. Dna was discovered in 1869 by a swiss biochemist, friedrich miescher. In most cases, they function as effectors for allosteric.
Nucleic acids are the acids found in cell nuclei and are involved in the transmission of genetic information. Nucleic acids are polymers specialized for the storage, transmission, and use of. Structural properties of nucleic acid building blocks function of dna and rna dna and rna are chainlike macromolecules that function in the storage and transfer of genetic information. Nucleic acids were named based partly on their chemical properties and partly on the observation that they represented a major constituent of the cell nucleus. Nucleic acids perform many functions essential for life, and exhibit a correspondingly diverse array of structures. Nucleic acids, built by polymerizing nucleotides, function primarily as informational molecules for the storage and retrieval of information about the primary sequence of polypeptides. That nucleic acids form the chemical basis for the transmission of genetic traits was not realized until about 50 years ago 1. Nucleic acids play important functions in the cell. Nucleic acid structure is often divided into four different levels.
Recommendations for the presentation of nmr structures of proteins and nucleic acids recommendations 1998 abstract. However, these compounds also serve many other functions in the cell. Deoxyribonucleic acid dna and ribonucleic acid rna are two major types of nucleic acids. Pdf the structure and function of nucleic acids revised. An overview of nucleic acid chemistry, structure, and function. Dna is identical most energy favorable conformation for double stranded dna to form without antiparallel base pairing this conformation could not exist structure consists of major grooves and minor grooves. The information from the base composition of dna, the knowledge of dinucleotide. Amino acids are imperative for sustaining the health of the human body. Two types of major nitrogenous bases, which account for the base composition of dna or. These are important organic substances found in nucleus and cytoplasm. Dna and rna are both nucleic acids, which are the polymeric acids isolated. Structures of nucleic acids some genomes are rna some viruses have rna genomes. Take the quiz or print the worksheet to assess what you have learned about the function and structure of nucleic acids. They are complex biopolymers containing a carbohydrate, a phosphate ester and a heterocyclic aromatic unit, the base.
All nucleic acids have the same fundamental structure. These relationships are summarized in table 71, and the corresponding chemical formulas are shown in figure 73. Pdf on jan 1, 2003, ludovic kurunczi and others published structure of biological macromolecules. Nucleic acids are macromolecules, huge polymers with molecular masses of over 100 million.
The nucleic acid associated protein, called nucleoprotein, together with the genome, forms the nucleocapsid. They must be supplied to our body through our diet. Nucleic acids rna and dna structure biochemistry youtube. Nucleic acids are defined as the polymers of nucleotide. Feb 06, 2012 nucleic acids structure and functions 1. Nucleic acids, deoxyribonucleic acid dna and ribonucleic acid rna, carry genetic information which is read in cells to make the rna and proteins by which living things function. Know the three chemical components of a nucleotide. Nucleic acid simple english wikipedia, the free encyclopedia. The chemical structures of the principal bases in nucleic acids. Function of rna dna has only one kind of function storing genetic information. These large molecules are called nucleic acids because they were first identified inside the nucleus of cells, however, they are also found in mitochondria and chloroplasts as well as bacteria and. Nucleosides in the hierarchy of nucleic acid structure, there are two more levels of nomenclature.
Secondary structure does not include bonding between the rgroups of amino acids, hydrophobic interactions, or other interactions associated with tertiary structure. The last portion of nucleic acids is the phosphate group. Figure 1 shows the structure of the nucleotides making up nucleic acids. Nucleic acids are longchain polymeric molecules, the monomer the repeating unit is known as the nucleotides and hence sometimes nucleic acids are referred to as polynucleotides. In the 1920s, it was discovered that nucleic acids was a major components of chromosomes. A nucleotide is made of a nitrogenous base, sugar with five carbon atoms and a phosphate group. A study of the structure and function of nucleic acids is needed to be able to understand how information controlling the characteristics of an organism is stored in the form of genes in a cell and how these genes are transmitted to future generations of offspring. Ppt nucleic acid powerpoint presentation free to view. The wellknown structure of the dna double helix allows this information to be copied and passed on to the next generation. The term nucleic acid is the overall name for dna and rna. Basically, nucleic acids can be subdivided into two types.
The assembly of nucleotides into polynucleotides, or nucleic acids, can be thought of as a dehydration reaction between the 3oh of one nucleotide and the phosphate group of a second nucleotide to form a phosphodiester bond. Importance of dnarna 3d structure nucleic acids are essential materials found in all living organisms. Read this article to get information about nucleic acids, its structure, size, types and significance. Discuss nucleic acids and the role they play in dna and rna. The main functions of nucleotides are information storage dna, protein synthesis rna, and energy transfers atp and nad. Learn vocabulary, terms, and more with flashcards, games, and other study tools. They are major components of all cells 15% of the cells dry weight. Molecular structure of nucleic acids a structure for. Dna contains a different ribose sugar and one of its four nitrogenous bases is different, but otherwise dna and rna are identical. Importance and chemical structure of nucleic acids science. The bestknown nucleic acid, dna, occurs in the form of a double helix. That nucleic acids form the chemical basis for the transmission of genetic traits was not realized until about 60 years ago 1,2.
Nucleotides are composed of a nitrogenous base, a fivecarbon sugar, and a phosphate group. Introduction to nucleic acids and their structure link. This group is of immense importance, as it is through this group that dna and rna are held together. Structure and function of nucleic acids slideshare. The nucleic acids are vital biopolymers found in all living things, where they function to encode, transfer, and express genes. Dna is a polymer of the four nucleotides a, c, g, and t, which are joined through a backbone of alternating phosphate and deoxyribose sugar residues. Although the nucleic acids were first discovered in 1868, by friedrich miescher working with pus cells obtained from discarded surgical bandages, it was not really until the early 1940s that the chemistry and biology of the nucleic acids were set on firm foundations. Basic structure four of five possible nitrogencontaining bases. The learning activities for this section include the. This structure has two helical chains each coiled round the same axis see diagram. The phosphoric acid component of each nucleotide is, of course, chemically identical in both nucleic acids. Read this article to learn about composition and structure of the nucleic acids.
Nucleic acids store and retrieve genetic information biology place tutorial 4. The three major rna species differ in their composition and function. Identify phosphoester bonding patterns and nglycosidic bonds within nucleotides. Hydrogen bonding interactions are especially important in nucleic acids. A variation of basepairing in nucleic acids such as the at pair two nucleobases, one on each strand, can be held together by hydrogen bonds in the major groove applies the n7 position of the purine base as a hydrogen bond acceptor and c6 amino group as a donor, which bind the watsoncrick n3n4 face of the pyrimidine base.
Proteins, carbohydrates, and lipids patrick charnay. By convention, nucleotide sequences are named in the 5 3 direction a nucleic acid has one 5end and one 3end. Resulting a repeating sugarphosphate backbone with protruding nitrogenous bases. Nucleic acids are polymers that consist of nucleotide residues. Proteins o the amino acids o the peptide bond o the protein conformation o the secondary structures. Nucleic acids are the biopolymers, or small biomolecules, essential to all known forms of life. Structure and function of nucleic acids as cell constituents.
Composition of nucleic acids a nucleic acid polymer, polynucleotide,forms from the nucleotide monomers when the phosphate of one nucleotide bonds to the sugar of the next nucleotide. Dna is a permanent storage place for genetic information. Importance and chemical structure of nucleic acids. Proteins determine how an organisms body is built and how it functions, which is why dna is often. Structural biochemistrynucleic acid wikibooks, open books. Both are composed of unbranched chains of units called nucleotides, each of which contains. Dna stands for deoxyribonucleic acid and rna stands for ribonucleic acid. Nucleic acids include ribonucleic acid, or rna, and deoxyribonucleic acid, or dna. Nucleic acids, macromolecules made out of units called nucleotides, come in two naturally occurring varieties. Amino acids properties, structure, classification and. Compare and contrast ribonucleotides and deoxyribonucleotides. All the genetic information is stored in the cell in the form of dna. In this article we summarise the structure and function of nucleic acids.
Nucleic acids are the main informationcarrying molecules of the cell, and, by directing the process of protein synthesis, they determine the inherited characteristics of every living thing. Dna deoxyribonucleic acid, and rna ribonucleic acid. In 1870, johann friedrich miescher was the first person that isolated the components of dna. Introduction to nucleic acids biology for majors i. Rna is a molecule of rather uniform composition with all four bases. B composition, structure and function of biomolecules carbohydrates, lipids, proteins, nucleic acids and vitamins.
Nucleotides and nucleic acids brief history1 1869 miescher isolated nuclein from soiled bandages 1902 garrod studied rare genetic disorder. Nucleic acids are formed by the combination of nucleotide molecules through sugarphosphate bonds known as phosphodiester linkages. A complete copy of your own dna can be found in the nucleus of almost every cell in your body, making this aggregation of dna called chromosomes in this context rather like the hard drive of a laptop computer. Nucleotides can be further broken down to phosphoric acid h 3 po 4, a pentose sugar a sugar with five carbon atoms, and a nitrogenous base a base containing nitrogen atoms. A nitrogenous base is connected to the carbon atom no. Nucleotides are the building blocks of nucleic acids.
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