Need help from an expert?
The world’s top online tutoring provider trusted by students, parents, and schools globally.
A cell translates mRNA into a polypeptide chain through a process called translation, which occurs in the ribosomes.
Translation is a key part of protein synthesis, the process by which cells produce proteins. It involves the decoding of the mRNA (messenger RNA) sequence into a polypeptide chain, which will later fold into an active protein. This process takes place in the ribosomes, which are the protein factories of the cell.
The process of translation can be divided into three stages: initiation, elongation, and termination. During initiation, the ribosome binds to the mRNA at the start codon (AUG) that is recognised by initiator tRNA. The ribosome then proceeds to decode the mRNA sequence into a polypeptide chain in the elongation stage. Each codon (a sequence of three nucleotides) on the mRNA corresponds to a specific amino acid. The ribosome moves along the mRNA, decoding its sequence and linking the corresponding amino acids together in a process facilitated by tRNA (transfer RNA) molecules. Each tRNA molecule carries a specific amino acid and has an anticodon that pairs with the codon on the mRNA.
The elongation process continues until the ribosome reaches a stop codon on the mRNA. At this point, the process of termination begins. The completed polypeptide chain is released, and the ribosome dissociates from the mRNA. The polypeptide chain then undergoes further processing and folding to become a functional protein.
It's important to note that multiple ribosomes can translate the same mRNA molecule simultaneously, creating multiple copies of the same protein. This process is known as polysome formation and allows for efficient protein synthesis.
In summary, the translation of mRNA into a polypeptide chain is a complex process that involves the coordinated action of ribosomes, mRNA, tRNA, and various other cellular components. It is a crucial part of protein synthesis, enabling cells to produce the proteins they need to function.
Study and Practice for Free
Trusted by 100,000+ Students Worldwide
Achieve Top Grades in your Exams with our Free Resources.
Practice Questions, Study Notes, and Past Exam Papers for all Subjects!
The world’s top online tutoring provider trusted by students, parents, and schools globally.