This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cellular Pathology, Subject name: Pathology
All are stop codon except? 
Select and explain. 
A. UAA, B. UGA, C. UAG, D. UCA
D: UCA
Answer: D: UCA 
Explanation: Ans. is 'd' i.e., UCA Stop codon (or termination codon)o In the genetic code, a stop codon is a nucleotide triplet within messenger RNA that signals a termination of translation into proteins.o Most codons in messenger RNA (from DNA) correspond to the addition of an amino acid to a growing polypeptide chain, which may ultimately become a protein. Stop codons signal the termination of this processo In the standard genetic code, there are three different stop codons:A) in RNA:i) UAG ("amber")ii) UAA ("ochre")iii) UGA ("opal")B) in DNA:i) TAG ("amber")ii) TAA ("ochre")iii) TGA ("opal" or "umber")