CHAPTER 2 BASICS OF MOLECULAR BIOLOGY

RNA RIBONUCLEIC ACID

RNA

Ribonucleic acid (RNA[1]) is a molecule similar toDNA[2] . Unlike DNA[2], RNA[1] is single-stranded. An RNA[1] strand has a backbone made of alternating sugar (ribose) and phosphate groups. Attached to each sugar is one of four bases--adenine (A), uracil (U[4]), cytosine (C), or guanine (G). Different types of RNA[1] exist in the cell: messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA). More recently, some small RNAs have been found to be involved in regulating Gene[3] expression.

The cell uses RNA[1]for a number of different tasks, one of which is called messenger RNA, or mRNA. And that is the nucleic acid information molecule that transfers information from the genome[5] into proteins by translation. Another form of RNA[1] is tRNA, or transfer RNA, and these are non-protein encoding RNA molecules that physically carry amino acids to the translation site that allows them to be assembled into chains of proteins in the process of translation.

Fondamental

  • RNA[1] is a biologically important type of molecule that consists of a long chain of nucleotide units.

  • Each nucleotide consists of a nitrogenous base, a ribose sugar, and a phosphate.

  • The four types of nitrogen bases are adenine (A[6]), uracil (U[4]), guanine (G[7]) and cytosine (C[8]).

  1. RNA : Ribonucleic Acid

  2. DNA : Deoxyribonucleic Acid

  3. Gene

    A gene is the basic physical and functional unit of heredity. Genes are made up of DNA. Some genes act as instructions to make molecules called proteins. However, many genes do not code for proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases.

  4. U : URACIL

  5. Genome

    A genome is all genetic material of an organism.

  6. A : ADENINE

  7. G : GUANINE

  8. C : CYTOSINE

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