Biology · Chromosomes and DNA
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In mitochondria, UGA codon act to specify ______ instead stop codon.
- A
Arginine
- B
Valine
- C
Glutamic acid
- D
Tryptophan
In mitochondria UGA codon is assigned to tryptophan (Trp) instead of being a signal for translational termination.
a) Arginine: This option suggests that the UGA codon in mitochondria specifies arginine instead of acting as a stop codon. However, this is not correct. In most organisms, including mitochondria, the UGA codon is recognized as a stop codon and signals the termination of protein synthesis.
b) Valine: This option suggests that the UGA codon in mitochondria specifies valine instead of acting as a stop codon. However, this is also not correct. Valine is typically specified by the codons GUA, GUC, GUG, and GUU.
c) Glutamic acid: This option suggests that the UGA codon in mitochondria specifies glutamic acid instead of acting as a stop codon. However, this is not correct. Glutamic acid is typically specified by the codons GAA and GAG.
UGA is a nonsense or termination (opal) codon throughout prokaryotes and eukaryotes. However, mitochondria use not only UGG but also UGA as a tryptophan codon
Tagged under Biology · Chromosomes and DNA · 2017