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Nucleoside and Nucleotide

Nucleic acids are the primary knowledge molecules in the cell, and ultimately define the hereditary properties of all living things by controlling the process of protein synthesis.

Nucleic acids are single- or double-stranded polynucleotides. Double-stranded polynucleotides are composed of two single-stranded polynucleotides that have been attached. Single-stranded polynucleotides are composed of a nucleoside monophosphate. Nucleosides are a group of organic compounds that are made of a nitrogenous base, a nine-member or six-member ring, and a five member pentose sugar.

About Nucleic Acids

Nucleic acids (NA) are organic compounds made up mainly of nitrogen, phosphorus, and carbon, that are essential in genetic information transfer. Nucleic acids are the building blocks of nucleic acid, or DNA, and RNA. They are the primary structure of DNA, which stores genetic information, and the genetic code. Nucleic acids are single-stranded polymers of nucleotides, which are linked via covalent bonds to form the nucleic acids.

Nucleotides or nucleic acids are a type of nucleic acid which contains a nitrogenous base covalently attached to a pentose sugar, making it a nucleoside. Nucleotides are the fundamental building blocks of DNA and RNA. Each nucleotide consists of a nitrogenous base covalently attached to a pentose sugar. The nitrogenous bases are adenine, cytosine, guanine, Uracil and thymine, while the pentose sugars are ribose (common to RNA only) and deoxyribose (common to DNA only).

Nucleic acids are the building blocks of RNA and DNA. These molecules are capable of storing and replicating information. They are found in every cell in our body. They have been used to great effect in the biotechnological and microbiology field, for example, in the study of viruses and bacteria.

Components of Nucleic Acids

DNA and RNA are nucleic acids, which are composed of four different classes of bases: adenine, cytosine, guanine, and thymine and Uracil(present only in RNA), or A, C, G, and T, U for short. Each nucleic acid consists of four bases, which are arranged in a specific order. Each nucleic acid, regardless of the type it is, contains a chain of the same four bases in a specific order. This makes up the backbone of the DNA or RNA. 

In the DNA of an organism, the sequence of nucleotide bases is the genetic code that determines all characteristics of that organism. Each cell in our body contains DNA and RNA. This DNA is the gene(s) that encode(s) the various proteins that are responsible for the function and maintenance of our body. 

Structure of Nucleic Acids

Nucleic acids are essential for life, and they are found in virtually all cells. DNA is the long molecule that stores genetic information, while RNA is the molecule that translates the code in DNA into the instructions that drive cellular activity. The chemical structure of nucleic acids is complex. It is also important to note that in addition to these two species of nucleic acids, there are other, smaller molecules in cells called nitrogen bases which provide an important contribution to the structure of DNA. DNA consists of two strands of a polynucleotide chain which is bonded to the other polynucleotide chain by hydrogen bonds; the presence of hydrogen bonds in the DNA confers major stability to its structure.  The nucleotides of each chain of the DNA  nucleotides stack on top of one another to produce the double helix structure.

The RNA molecule consists of only a single polynucleotide chain which is universally composed of Carbon, Hydrogen, and Nitrogen atoms. RNA is a relatively unstable molecule due to the absence of hydrogen bonds. The primary difference between A DNA and RNA molecule is the presence of Uracil pyrimidine. 

Difference between Nucleosides and Nucleotides

Nucleoside

  • Nucleosides composition is given by- Nitrogen base + Pentose sugar
  • The nitrogenous base is a purine or a pyrimidine, while the sugar is a monosaccharide such as deoxyribose, or ribose. Nucleosides are the components of nucleic acid and they are composed of a nucleobase and a sugar
  • The sugar is either monosaccharide or disaccharide, and the nucleobase is either purine or pyrimidine
  •  Nucleosides have a characteristic chemical property. In nucleosides, a sugar is always paired with a nucleobase
  • Nucleosides are organic molecules that serve as the building blocks of nucleotides. The nucleosides are composed of one of the four naturally occurring bases and a pentose sugar deoxyribose or ribose
  • Nucleosides present in nucleic acids are Adenosine, Guanosine, Cytidine, Thymidine, and Uracil

Nucleotide

  • The composition of nucleotides is given by – Nucleoside + Phosphate group or Nitrogen Base + Pentose sugar + Phosphate group
  • A nucleotide is made up of a purine or pyrimidine base (the one that is paired with another purine or pyrimidine base), a ribose sugar, and a phosphate group
  • There are different nucleotides based on the number of phosphate groups attached to the nucleosides the most common nucleotides being adenosine triphosphate (ATP), cytosine triphosphate (CTP), guanosine triphosphate (GTP), and thymidine triphosphate (TTP) and uridine Triphosphate (UTP)
  • Nucleotides are the building blocks of all nucleic acids and are the active form of nitrogen bases. Each nucleotide contains a nitrogenous base attached to a sugar and a variable number of phosphate groups
  •  The sugar is either deoxyribose (DNA) or ribose (RNA). A standard nucleotide contains one of four nitrogenous bases. They are present in each of a double stranded chain of nucleic acid

Conclusion

Nucleic acids are a group of biopolymers made from nucleotides. Their primary function is to carry genetic information. The DNA is a double helix, with each strand composed of four bases, the nucleotides. This structure allows the sequence of the bases in one strand to be complementary to the sequence of bases in the other strand.

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What are nucleic acids and what is their role in the cells and body of living organisms?

Answer: Nucleic acids are a class of biomolecules that are found in all organisms and viruses. Nucleic acid activities include the storage and expr...Read full

What is the most noticeable difference between nucleoside and nucleotide?

Answer: A nucleoside comprises nitrogen bases (A,T,G,C,U) and pentose sugars. While the nucleotide consists of a nuc...Read full

What is the chief difference between the structure of DNA and RNA?

Answer: The structure of DNA consists of two polynucleotide chains intertwined...Read full