Answer:
1.RNA polymerase unzips DNA and free RNA nucleotides join DNA to form mRNA.
2. mRNA is transported from the nucleus of the cell to the ribosomes of the cell.
3. mRNA joins the ribosome, and the anticodons from tRNA join mRNA to form a chain of amino acids
4. A chain of amino acids is formed from peptide bonds, creating a protein
5. Once the protein is made, the gene for a particular trait is expressed
Explanation:
The process of gene expression involves the production of gene products (usually proteins). Gene expression occurs in two distinct stages namely: transcription and translation. Transcription, which occurs in the nucleus of eukaryotic cells, is the first step of protein synthesis. It involves the copying of the genetic information present in a DNA molecule into a RNA molecule.
Transcription begins when an enzyme called RNA polymerase binds to the promoter region on the DNA molecule. This process is called INITIATION. This binding signals the double-stranded DNA to unwind, allowing the RNA polymerase to synthesize/add nucleotides that are complementary to what it reads on the DNA to the mRNA molecule.
After transcription, the mRNA transcript is transported out of the nucleus into the cytoplasm, specifically the RIBOSOME (organnelle for protein synthesis). The mRNA attaches to the ribosomes, triggering the initiation of translation (second stage of protein synthesis). Transfer RNA (tRNA) in the ribosome binds to the mRNA molecule and uses its ANTICODON (complementary nucleotides to the mRNA codon) to read the nuceleotide of the mRNA in order to carry the corresponding amino acid to the growing polypeptide chain.
As each amino acid is added by the tRNA based on the nucleotide it reads on the mRNA codon, a PEPTIDE BOND is formed by the combination of two amino acids forming a polypeptide, which is eventually released as a protein at the end of the translation process.
Once a gene is successfully used to synthesize a protein, it is said that have being expressed.
