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  1. There are two key components of translation (Protein synthesis): ribosomes and transfer RNA
  2. The Ribosomes are cellular particles also known as ribonucleoprotein.
  3. It is a highly specialized and complex structure.
  4. For the synthesis of protein, a cell needs ribosomes.
  5. They connect one amino acid to another and forms a long string like structure called as polypeptide.
  6. Ribosomes are themselves composed of a complex of proteins and specialized RNA molecules called ribosomal RNA (rRNA).
  7. The mRNA comprises a series of codons that dictate to the ribosome the sequence of the amino acids needed to make the protein.
  8. Many ribosomes can simultaneously translate an RNA molecule, which increase the efficiency of mRNA utilization.
  9. The group of ribosomes bound to an mRNA molecule is known as “Polyribosome or simply polysome or rarely an ergosome.
  10. Using the mRNA as a template, the ribosome traverses each codon of the mRNA, pairing it with the appropriate amino acid provided by a tRNA.
  11. There are two ribosomal units required for the initiation of protein synthesis. They are: 30S ribosomal unit and 50S ribosomal unit.
  12. 30S subunit is responsible for the starting of initiation complex where as 50S subunit is responsible for the completion of initiation complex.
  13. There are three sites of a ribosome for the elongation process: new tRNA enters from “A site (aminoacyl)”, “P site (peptidyl) contains a peptidyl tRNA and “E site (exit)” contains an uncharged tRNA.
  14. In this way ribosomes are essential for the translation process.
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