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. As we have already studied nucleic acids are one of the most important biomolecules present in humans. Nucleic acids were first discovered by friedrich miescher in 1871. Nucleic acid function and basics the function of dna and rna is to store genetic information. The term nucleic acid is the overall name for dna and rna. 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. Based on side chain structure, amino acids can be divided into four groups. In this section, we will examine the structures of dna and rna, and how these structures are related to the functions these molecules perform.
They store all our genetic information that we pass down to future generations. If the sugar is a compound ribose, the polymer is rna ribonucleic acid. This article covers the chemistry of nucleic acids, describing the structures. Helicase activity was monitored by detecting the unwinding of a dna hairpin with an optical trap, as described previously 20, 21. Like other macromolecules, nucleic acids are composed of monomers, called nucleotides, which are polymerized to form large strands. Structure and function of nucleic acids flashcards quizlet. Nucleic acids are essential to life, and this quizworksheet will help you check your understanding of many of the key terms and concepts relating to them. 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. Nucleic acids are the main informationcarrying molecules of the cell and play a. The two main types of nucleic acids are deoxyribonucleic acid dna and ribonucleic acid rna. The key concept is that some form of nucleic acid is the genetic material, and these encode the macromolecules that function in the cell. Erwin chargaff was a pioneer that tried to construct the composition of dna. Nucleic acids with video tutorials and quizzes, using our many waystm approach from multiple teachers. Nucleic acids are macromolecules, huge polymers with molecular masses of over 100 million.
The rapid developments in the area of genetic engineering and recombinant dna. Pdf this presentation clarify the basic structure of nucleic acids,types, differences. Structure and function of nucleic acids as cell con. The structure of dna more than ever become a universal interest in scientic world. Read this article to learn about composition and structure of the nucleic acids. It has many functions in cells, notably acting as the intermediate between dna and proteins. 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. Each nucleic acid strand contains certain nucleotides that appear in a.
The depicted threedimensional structures focus on the bulgedg motif region red box in secondary structure where all three algorithms fail. They are composed of nucleotides, which are the monomers made of three components. Structural biochemistrynucleic acid wikibooks, open. They are believed to be the first biomolecules to support life as it is typically defined. Dna is metabolically and chemically more stable than rna. Pdf an overview of nucleic acid chemistry, structure, and function. Proteins and nucleic acids structure and function perutz, m.
They are linked together by a peptide bond see later. Nucleic acid structure is often divided into four different levels. Nucleic acids are the most important macromolecules for the continuity of life. The structure of nucleic acids as polymers with unique sequences of bases by way of their nucleotide residues gives way to a high fidelity means of transmitting genetic information by reading and replicating the base sequence for a strand of dna. Composition, structure, and function, volume iii, second edition is a collection of papers that deals with the proteins of antibodies and antigens, of the blood clotting system, plasma proteins, and the virus proteins. Function of rna dna has only one kind of function storing genetic information. Continued folding of polypeptide beyond secondary structure b. Caused by attractions between r groups of amino acids c.
Their main function is to maintain and transmit the genetic code. The backbone of a nucleic acid is made of alternating sugar and phosphate molecules bonded together in a long chain, represented below. In microbial metabolism, we discussed three classes of macromolecules. Nucleotides are composed of a nitrogenous base, a fivecarbon sugar, and a phosphate group. Going from 5 to 3 of one strand means going from 3 to 5 of the other strand. These molecules are composed of long strands of nucleotides. Both are composed of unbranched chains of units called nucleotides, each of which contains. 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. The backbone of a nucleic acid molecule is formed by the repeating sequence of pentose and phosphate groups, and this is the same in all molecules. They carry the genetic blueprint of a cell and carry instructions for the functioning of the cell. This lesson presents how the structure and function of nucleic acids pertain to living things. Dna polymerase requires a short doublestranded region with a free 3. Chapter 2 structures of nucleic acids nucleic acids. Resulting a repeating sugarphosphate backbone with protruding nitrogenous bases.
We explain structure and function of macromolecules. Nucleic acids are the biopolymers, or small biomolecules, essential to all known forms of life. Nucleic acids are polymers that consist of nucleotide. In this section, we will examine the structures of dna and rna, and how these structures are related to the. Direct observation of structurefunction relationship in a. This volume consists of five chapters that specifically cover the advances in understanding the structure and function of. He found that the amount of adenine a always equaled the amount of thymine t, and the amount of guanine g always equaled the amount of cytosine c. Composition, structure, and function, second edition, volume ii deals with fundamental properties of proteins, both in solution and in the solid state. In rna, the pentose is ribose, whereas in dna it is 2deoxyribose.
Dna is a permanent storage place for genetic information. Function of nucleic acids the purpose of dna is to act as a code or recipe for making proteins. Secondary structure is the set of interactions between bases, i. The 2 singlestrands are antiparallel to each other. The two main classes of nucleic acids are deoxyribonucleic acid and ribonucleic acid.
This biochemistry video tutorial provides a basic introduction into nucleic acids such as dna and rna. An overview of nucleic acid chemistry, structure, and function. Dna stands for deoxyribonucleic acid and rna stands for ribonucleic acid. 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. Structure and function of biomolecules 16 amino acids amino acids are bifunctional compounds containing both a carboxylic acid group cooh and a basic amino group nh2 attached to the same carbon atom fig. The proteins composition, structure, and function v3 2nd. The secondary structure is responsible for the shape that the nucleic acid assumes. In most cases, they function as effectors for allosteric. Viruses also contain nucleic acids, however, unlike a plant or animal has either rna or dna, but not both. Nucleic acids are long chainlike molecules composed of a series of nearly identical building blocks called nucleotides. Start studying structure and function of nucleic acids. Nucleic acids are polymers that consist of nucleotide residues. They are major components of all cells 15% of the cells dry weight. Adenine and guanine are doublering structures termed purines.
What is a nucleic acid definition, structure and composition, function, examples 2. 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. 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. Side chains with basic groups arginine, lysine, and histidine are called basic amino acids because their side chains are proton acceptors figure 2. Learn vocabulary, terms, and more with flashcards, games, and other study tools. A study of the structure and function of nucleic acids is needed to be. Dna is found mainly as a component of chromatin material of the cell nucleus whereas most of the rna 90% is present in the cell cytoplasm and the remaining 10% in the nucleolus. Proteins determine how an organisms body is built and how it functions, which is why dna is often. Nucleic acids and chromatin openlearn open university. The double in the double helix means that dna is found in a doublestranded form 2 singlestranded chains of dna stuck to each other via hydrogen bonding of the base pairs.
The main difference between nucleotide and nucleic acid is that nucleotide is the monomer of nucleic acid whereas nucleic acid is a chain of nucleotides, which is capable of storing genetic information in the cell. A small protein with a high proportion of positively charged amino acids that binds to the negatively charged dna and plays a key role in its chromatin structure. The guanidino group in arginines side chain is a relatively strong. Structure and function nucleic acids biology libretexts. They are members of a family of biopolymers essential for life, and include dna and rna. The nucleotides on one strand base pairs with the nucleotide on the other strand. The proteins composition, structure, and function v2 2nd.
Ppt nucleic acid powerpoint presentation free to view. Nucleic acids are macromolecules that store genetic information and enable protein production. Made of two or more folded polypeptides joined together c. Nucleic acids are molecules that store and transmit hereditary information and energy in living things. This information is stored in the form of long polymer chains. The chemical structure of repeating nucleotide subunits in dna and rna. The wellknown structure of the dna double helix allows this information to be copied and passed on to the next generation. The nucleic acids, dna and rna, may be thought of as the information molecules of the cell. Nucleic acid structure refers to the structure of nucleic acids such as dna and rna. Structures of nucleic acids some genomes are rna some viruses have rna genomes. 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. The wellknown structure of the dna double helix allows this information to be. He wanted to determine the chemical composition of leucocytes white blood cells, his. Although the information they carry is onedimensional, it is essential to understand the 3d structure of nucleic acids.
Nucleic acids were first isolated from the cellular nucleus, hence the name. In this chapter, we will discuss a fourth class of macromolecules. The composition and conformation of the same uvrd unwinding complexes, sitespecifically labeled with. In 1953, a team including james watson, francis crick and rosalind franklin accurately described the structure of dna, or deoxyribonucleic acid. Describe the primary structure of dna and rna and secondary and tertiary. Dna is the genetic material found in all living organisms, ranging from singlecelled bacteria to multicellular mammals. The nucleic acids are vital biopolymers found in all living things, where they function to encode, transfer, and express genes. In dna double helix, the two strands of dna are held together by hydrogen bonds. The structure and function of nucleic acids biochemical society. And they are able to perform their functions, due to the shape and structure they form.
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