The process by which proteins are synthesized within cells is called protein synthesis. Protein synthesis involves two main steps: transcription and translation.
During transcription, the DNA sequence of a gene is converted into a messenger RNA (mRNA) molecule. This process occurs in the nucleus of eukaryotic cells and in the cytoplasm of prokaryotic cells. The enzyme RNA polymerase binds to the DNA and synthesizes a complementary RNA molecule, following the base-pairing rules (A pairs with U and G pairs with C).
Once the mRNA molecule is synthesized, it undergoes processing to remove non-coding regions called introns and to add a protective cap and a poly-A tail. The resulting mature mRNA molecule is then transported out of the nucleus and into the cytoplasm.
Translation, the second step of protein synthesis, takes place in the cytoplasm and involves the assembly of amino acids into a polypeptide chain according to the information encoded in the mRNA molecule. Ribosomes, which consist of ribosomal RNA (rRNA) and proteins, bind to the mRNA and read its sequence in sets of three nucleotides called codons. Each codon corresponds to a specific amino acid or a signal for the start or end of protein synthesis.
Transfer RNA (tRNA) molecules carry the corresponding amino acids to the ribosome and bind to the codons on the mRNA through their complementary anticodons. The ribosome facilitates the formation of peptide bonds between the amino acids, building the polypeptide chain. The process continues until a stop codon is reached, signaling the termination of protein synthesis. The newly synthesized protein is then folded into its functional structure and may undergo additional modifications before it is ready to perform its specific cellular functions.
What is the process by which proteins are synthesized within cells?
Photosynthesis
Protein Synthesis
Glycolysis
Protein Digestion
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