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Nucleic acids
The primary structure of DNA - is a linear sequence of nucleotides in the
chain. Usually the sequence is written in the form of letters (eg
AGTCATGCCAG), moreover recording is carried out with a 5'- 3' - end of the
chain.
Secondary structure - a structure formed at the expense of non-covalent
interactions of nucleotides (mostly nitrogen bases) with each other, stacking and
hydrogen bonding.
a classic example of the secondary structure - DNA double helix. It is most
common in nature, its shape, consisting of two complementary polynucleotide
chains anti paralel. Antiparallel realized due to the polarity of each of the chains.
Under the complementarity understand each line of nitrogenous bases of one
strand of DNA is strictly certain other chain base (opposite A is T, and G is
located opposite the C).
DNA is retained in double helix due to complementary base pairing - the
formation of hydrogen bonds, two in the pair of A-T and three paired G-C.
In 1868, Swiss scientist Friedrich Miescher isolated from cell nuclei of
phosphorus-containing substance, which he called nucleic.
Later, this and similar substances are called nucleic acids. Their molecular
weight can be up to 109, but usually ranges from 105-106.
The starting materials, which are built from nucleotides - units
macromolecules nucleic acids are: carbohydrate, phosphoric acid, purine and
pyrimidine bases.
In one group of acids as carbohydrate ribose appears in the other -
deoxyribose
In accordance with the nature of the carbohydrates in their composition,
nucleic acid called ribonucleic and deoxyribonucleic acid
Commonly used abbreviations are RNA and DNA. Nucleic acids are the
most responsible role in life processes.
With their help solve two major problems: the storage and transmission of
genetic information, and matrix synthesis of DNA macromolecules, RNA and
protein.
A significant proportion of the total output of modern meat processing
industry sausage products occupy emulsified meat products and a wide range of
products, such as sausages, small sausages - grilled, boiled and ham - chopped
sausages and other combination of meat products including bacon, meal, meat,
pieces of offal, vegetables, etc.
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