There are sixty-one mRNA codons that specify an amino acid, but only forty-five tRNAs. This is best explained by the fact that

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Explanation:

The phenomenon is best explained by the fact that the genetic codes are degenerates. In other words, more than one codon can specify for the same amino acid being carried by the tRNA.

The base-pairing rule between the third nucleotide of a codon and that of the anticodon on the tRNAs loosens off. For example, GUU, GUC, and GUA all specify for the amino acid valine while GCU, GCC, and GCA all specify for alanine.

one centimetre is equal to 0.01 metres

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.