Translation

Definition

Translation is the process by which the genetic code carried by messenger RNA (mRNA) is converted into a sequence of amino acids to form a protein. This critical step in gene expression occurs in the ribosome, where tRNA molecules bring specific amino acids to the growing polypeptide chain, according to the codons specified by the mRNA. Translation connects the information stored in DNA with the functional proteins that carry out cellular tasks.

5 Must Know Facts For Your Next Test

1. Translation occurs in three main stages: initiation, elongation, and termination, each with specific roles in assembling the protein chain.
2. Each tRNA molecule has an anticodon that pairs with the corresponding codon on the mRNA, ensuring that the correct amino acid is added to the growing polypeptide.
3. The ribosomal subunits come together during translation initiation, forming a functional ribosome capable of synthesizing proteins.
4. Translation can occur simultaneously with transcription in prokaryotes since they lack a nuclear membrane, allowing for rapid protein production.
5. Post-translational modifications may occur after translation, altering the newly formed protein's structure and function for specific roles within the cell.

Review Questions

• How does the structure of tRNA facilitate its function during translation?
  • The structure of tRNA includes an anticodon region that pairs with specific codons on the mRNA strand, which ensures accurate translation of genetic information into proteins. Additionally, each tRNA carries a specific amino acid corresponding to its anticodon, allowing it to deliver the correct building block to the growing polypeptide chain. This unique structure is crucial for maintaining fidelity during protein synthesis.
• Discuss the importance of ribosomes in translation and how they contribute to protein synthesis.
  • Ribosomes are essential cellular structures that facilitate translation by providing a site where mRNA and tRNA interact to synthesize proteins. They consist of two subunits that come together around an mRNA molecule during initiation. The ribosome moves along the mRNA strand, catalyzing peptide bond formation between amino acids brought by tRNA, thus translating genetic information into functional proteins efficiently.
• Evaluate how errors during translation could affect protein synthesis and overall cellular function.
  • Errors during translation can lead to the incorporation of incorrect amino acids into a protein, resulting in misfolded or nonfunctional proteins. Such mistakes can disrupt cellular processes and lead to diseases or dysfunctions. For instance, a single incorrect amino acid in hemoglobin can cause conditions like sickle cell anemia, highlighting the critical importance of accuracy during translation for maintaining healthy cellular functions.

Related terms

transcription:

Transcription is the first step in gene expression, where a segment of DNA is copied into messenger RNA (mRNA) by the enzyme RNA polymerase.

codon:

A codon is a sequence of three nucleotides in mRNA that specifies a particular amino acid or signals the termination of translation.

ribosome: The ribosome is a complex molecular machine within cells that facilitates the process of translation by reading mRNA and synthesizing proteins.