Nucleic acids Ribonucleic acid

Nucleic acids are acidic substances present m the nuclei of cells and were known long before anyone suspected they were the primary substances involved m the storage transmission and processing of genetic information There are two kinds of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) Both are complicated biopolymers based on three structural units a carbohydrate a phosphate ester linkage between carbohydrates and a heterocyclic aromatic compound The heterocyclic aro matic compounds are referred to as purine and pyrimidine bases We 11 begin with them and follow the structural thread... 

Nucleic acids are the molecules in our cells that direct and store information for reproduction and cellular growth. There are two types of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). Both of these nucleic acids are unbranched organic polymers composed of monomer units called nucleotides. These nucleotides are composed of a sugar molecule, a nitrogen base, and phosphoric acid. A single DNA molecule may contain several million of these nucleotides, while the smaller RNA molecules may contain several thousand. 

Deoxyribonucleic acid (DNA) serves as a template for the synthesis of nucleic acids. Ribonucleic acid (RNA) executes protein synthesis and thus permits cell growth. Synthesis of new DNA is a prerequisite for cell division. Substances that inhibit reading of genetic information at the DNA template damage the regulatory center of cell metabolism. The substances listed below are useful as antibacterial drugs because they do not affect human cells. 

The major nucleic acid in the nucleus of cells is deoxyribonucleic add (or DNA). It contains the pentose sugar deoxyribose as one of its chemical constituents. DNA is now known to be the genetic material. Another type of nucleic acid, ribonucleic acid (or RNA), contains ribose instead of deoxyribose. Its main role is in the transmission of the genetic information from DNA into protein. 

These purines and pyrimidines join to the sugar-phosphate backbones of nucleic acids through repeating /3-linked AT-glycosidic bonds involving the N9 position of purines and the N1 position of pyrimidines. There are two classes of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). DNA and RNA differ in one of their nitrogenous base components (uracil in RNA, thymine in DNA) and in their sugar (ribose) moiety, as indicated in Fig. V-2. 

Our proteins determine what our cells do. However, our DNA determines what these proteins are made of A gene is a segment of DNA that has the code for the amino acid sequence to build a polypeptide. The way that the gene is translated into an amino-acid sequence is elaborate. It uses many proteins and another nucleic acid, ribonucleic acid, or RNA. 

There are two types of nucleic acids ribonucleic acid (RNA) and deox)tribonucleic acid (DNA). One of the ways in which they differ is in the carbohydrate that they contain. 

One of the major achievements in all of science has been the identification, at the molecnlar level, of the chemical interactions that are involved in the transfer of genetic information and the control of protein biosynthesis. The substances involved are biological macromolecnles called nucleic acids. Nucleic acids were isolated over 100 years ago, and, as their name implies, they are acidic substances present in the nuclei of cells. There are two major kinds of nucleic acids ribonucleic acid (RNA) and deoxyribonucleic acid (DNA). To understand the complex structure of nucleic acids, we first need to examine some simpler substances, nitrogen-containing aromatic heterocycles called pyrimidines and purines. The parent substance of each class and the numbering system used are shown ... 

The mechanism by which genetic information is decoded and used to direct cellular processes begins with the synthesis of another type of nucleic acid, ribonucleic acid (RNA). RNA synthesis occurs by complementary pairing of ribonucleotide bases with the bases in a DNA molecule. 

Monomer Structure and Linkage Nucleic acids are polynucleotides, unbranched polymers that consist of mononucleotides, each of which consists of an N-containing base, a sugar, and a phosphate group. The two types of nucleic acid, ribonucleic acid (RNA) and deoxyribonucleic acid (DNA), differ in the sugar portions of their mononucleotides RNA contains ribose, and DNA contains deoxyribose, in which —H substitutes for —OH on the second C of ribose. 

DNA (DeoxyriboNucleic Acid) is called the genetic material because it contains the genetic information for every cell and tissue in an organism. DNA is a component of the chromosomes (proteins are the other component). DNA is one of two types of nucleic acid. Ribonucleic acid (RNA) is the other. As such, DNA is a polymer of deoxyribonucleotides linked through phosphodiester bonds (Figure 4,1). 

Transmission and coding of this information into proteins. These processes, called transcription and translation, are mediated by a second class of nucleic acids, ribonucleic acid (RNA). 

When a cell requires protein, another type of nucleic acid, ribonucleic acid (RNA), interprets the genetic information in DNA and carries that information to the ribosomes, where the synthesis of protein takes place. However, mistakes may occur that lead to mutations that affect the synthesis of a certain protein. 

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