Answer:
I. tRNA anticodon bonds to mRNA codon
II. Ribosome bonds to mRNA strand
III. Ribosome reaches a STOP codon and detaches from the mRNA
IV. Each tRNA adds an Amino Acid to the chain as the Ribosome moves along the mRNA
Explanation:
Translation is the second process of gene expression in which a protein molecule is synthesized from the information in a mRNA strand. Translation occurs in the RIBOSOME (an organnelle for protein synthesis made up of ribosomal RNA (rRNA) and proteins). The process of translation occurs in three stages viz: Initiation, Elongation and Termination.
Initiation occurs when the ribosome binds to the mRNA strand in the cytoplasm. The mRNA sequence is then read in a group of three nucleotides called CODON by the ANTICODON of a transfer RNA (tRNA). The basis of reading is the complementary base pairing rule i.e. A-U, G-C. Options I and II describes this stage.
In the elongation stage, the tRNA carries an amino acid corresponding to what it reads in the mRNA codon to the growing polypeptide chain. The amino acids bonds to one another via a peptide bond. As each codon is being read, the mRNA gradually moves over the means sequence. Option IV describes this stage.
Elongation stage continues until any of the stop codons (UAA, UAG, and UGA) are finally encountered by the trans in the ribosome. Since, there are no corresponding anticodons that can read the stop codons, they signal the termination of the translation process. The ribosome then detaches from the mRNA sequence. Option III describes this stage.
Note, option V describes TRANSCRIPTION not TRANSLATION.
