Which best summarizes the process of protein synthesis? a.RNA instructs DNA to make proteins. b.DNA unzips, resulting in the formation of two protein molecules. c.RNA moves the DNA code to the ribosomes for protein synthesis. d.DNA makes proteins in the nucleus…
The Correct Answer and Explanation is :
The best summary of the process of protein synthesis is c. RNA moves the DNA code to the ribosomes for protein synthesis.
Explanation of Protein Synthesis
Protein synthesis is a vital biological process through which cells produce proteins, which are essential for numerous cellular functions. This process can be divided into two main stages: transcription and translation.
- Transcription: The process begins in the nucleus of a cell, where DNA serves as a template for synthesizing messenger RNA (mRNA). During transcription, specific segments of DNA unwind and uncoil, allowing RNA polymerase to read the DNA sequence and synthesize a complementary strand of mRNA. This mRNA strand carries the genetic information from the DNA, effectively encoding the sequence of amino acids that will form a protein. Once the mRNA is synthesized, it undergoes processing, which includes adding a 5’ cap and a poly-A tail, and the removal of introns (non-coding regions), resulting in a mature mRNA molecule.
- Translation: After transcription, the mature mRNA exits the nucleus and travels to the ribosomes, which can be found in the cytoplasm or on the rough endoplasmic reticulum. Here, the ribosomes read the mRNA sequence in sets of three nucleotides, known as codons. Each codon corresponds to a specific amino acid. Transfer RNA (tRNA) molecules, each carrying an amino acid, bind to the ribosome at the appropriate codon, facilitating the addition of amino acids to the growing polypeptide chain. This chain continues to elongate until a stop codon is reached, signaling the end of protein synthesis. The newly synthesized protein then folds into its functional shape, allowing it to perform its specific roles within the cell.
In summary, protein synthesis is a complex, multi-step process involving transcription of DNA into mRNA and translation of that mRNA into a functional protein at the ribosomes, highlighting the essential role of RNA in conveying genetic information from DNA to the sites of protein synthesis.