Deoxyribonucleic acid molar mass

Within every living cell, there is an organic natural polymer called deoxyribonucleic acid or, more commonly, DNA. The DNA molecule is enormous its molar mass is estimated to be of the order of 2 x 1010 g. The molecule takes the form of a narrow, tightly coiled band, which, if straightened out, would have a length of about 1 m. 

The substance that stores and transmits the genetic information is a polymer called deoxyribonucleic acid (DNA), a huge molecule with a molar mass as high as several billion grams. Together with other similar nucleic acids called the ribonucleic acids (RNA), DNA carries the information needed for the synthesis of the various proteins the cell requires to carry out its life functions. The RNA molecules, which are found in the cytoplasm outside the cell nucleus, are much smaller than DNA polymers, with molar mass values of only 20,000 to 40,000 grams. 

Equilibrium sedimentation studies are mostly used to investigate density differences in different macromolecules. The method has been used, for example, in research on the replication of N-labeled deoxyribonucleic acids. Theoretically, it is also suitable for distinguishing between polymer blends and true copolymers. In such studies, problems usually arise from the considerable back-diffusion and the wide molar mass distribution. The gradient curves are so strongly influenced by these two effects that there is considerable overlap in the curves for substances of differing densities. 

Deoxyribonucleic acids possess between several thousand and several thousand million base pairs per molecule (Table 29-3). The molar masses vary correspondingly from several million upwards. The extremely high complexity is characteristic for DNAs. Here, the complexity is defined as the number of base pairs that are in nonrepeating sequences. The complexity of simple natural DNAs is already about 10 -10. ... 

Nucleic acids are high-molar-mass polymers that play an essential role in protein synthesis. Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are the two types of nucleic acid. DNA molecules are among the largest molecules known they have molar masses of up to tens of billions of grams. RNA molecules, on the other hand, vary greatly in size, some having a molar mass of about 25,000 g. Compared with proteins, which are made of up to 20 different amino acids, nucleic acids are fairly simple in composition. A DNA or RNA molecule contains only four types of building... 

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