Describe what occurs during protein synthesis.

Describe the whole process of protein synthesis...?

• Describe the whole process of protein synthesis beginning from the nucleus to the cytoplasm and finally ending at the ribosome. Please help me. Thank you.

• Answer:

  Protein synthesis relies on the effective communication of the coded information held in the genes to the sites of protein manufacture, the ribosomes in the cytoplasm.Since DNA is part of larger structures(chromosomes), which are unable to move from the nucleus, intermediate messenger molecules are needed. These are messenger RNA molecules. To begin with, the DNA duplex unzips to expose the base sequence on the coding strand. RNA nucleotides then move in and align themselves according to the rules of base pairing (A-U and G-C) with U replacing T in the RNA molecule.The RNA is assembled using the enzyme RNA polymerase. This process is called transcription.The completed mRNA molecule detaches from the DNA template and exits the nucleus via the nuclear pores, moving into the cytoplasm. The mRNA is now ready for translation, which is organised by the ribosomes, which now attach themselves to the mRNA.The ribosome attaches to the mRNA by its small subunit. Magnesium ions are involved in the attachment process.The larger subunit of the ribosome can accommodate two codons of the mRNA. One is held in the P (peptidyl) site and the other in the A (aminoacyl) site. Each codon triplet then attracts a complementary triplet or anticodon. Each anticodon forms part of one transfer RNA (tRNA) molecule. Each tRNA carries one specific amino acid in the cytoplasm. The anticodon and codon bind together temporarily by means of hydrogen bonds.This causes two amino acids to be held next to one another long enough for the formation of a peptide bond between them.The formation of the peptide bond is catalysed by the enzyme peptidyl transferase, which is an integral part of the large ribosome subunit.