Which of the Following is True About the Genetic Code

Question

Which of the following is true about the genetic code?  
A) All organisms use essentially the same genetic code.
B) The codon signaling the end of transcription also codes for an amino acid.
C) There are multiple codons signaling the start of transcription.
D) Each amino acid is specified by only one codon.
E) A codon is three to six bases long.

Accepted Answer

All organisms use essentially the same genetic code, with a few minor exceptions. This means that the same codons specify the same amino acids across different organisms, allowing for universal understanding of genetic information.

Answer: B 
 The codon signaling the end of transcription is called a stop codon (UAA, UAG, or UGA) and it does not code for an amino acid.

Answer: C 
 There is only one start codon, AUG, which signals the start of translation, not transcription.

Answer: D 
 Most amino acids are specified by more than one codon, except for methionine and tryptophan which have only one codon each.

Answer: E 
 A codon is always exactly three bases long, never six or any other number.