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Biology

RNA and protein synthesis

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The structure of RNA

RNA nucleotides joined by phosphate forming RNA. On each nucleotide, the phosphate is joined to ribose which is attached to a base.

RNA is a type of nucleic acid called ribonucleic acid:

  • The RNA nucleotides [nucleotide: a molecule built from a nitrogenous base (base containing nitrogen), a 5-carbon sugar (a pentose sugar) and a phosphate group are joined to form a single strand.
  • The nucleotides are joined by a bond between the sugar of one nucleotide and the phosphate of the next.

RNA differs from DNA in the following ways:

  • RNA is single stranded while DNA is double stranded.
  • RNA has a sugar called ribose while DNA has a sugar called deoxyribose.
  • RNA has the base uracil while DNA has the base thymine.

There are two types of RNA that need to be known for this topic. The first is messenger RNA, or mRNA. This is formed in the nucleus of the cell [cell: Basic unit of life. Unicellular organisms only have one cell. Multicellular organisms have many cells.. It rewrites the sequence of bases of a section of DNA in a process called transcription.

mRNA carries the code for building a specific protein from the nucleus to the ribosomes in the cytoplasm [cytoplasm: The living substance inside a cell (not including the nucleus).. That is, it acts as a messenger.

The second is transfer RNA, or tRNA. This is found in the cytoplasm.

The tRNA picks up specific amino acids [amino acids: Complex molecules, which form the building-blocks of proteins. from the cytoplasm and brings them into position on the surface of a ribosome where they can be joined together in specific order to make a specific protein.

This process is called translation.

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