How many aminoacyl-$t-\mathrm{RNA}$ synthetases are present for each of the $20$ common amino acids?

Draw three-dimensional representations of the following amino acids.

(b) L-histidine

Draw three-dimensional representations of the following amino acids.

(c) D-serine

Draw three-dimensional representations of the following amino acids.

(d) L-tryptophan

The first amino acid in the pentapeptide of Figure 26.50, Pyr, is not one of the 20 amino acids in Table 26.1. Based on the following structure of Pyr, from which natural amino acid is it likely derived?

In a given sample analysis, which amino acid is present in higher amounts than $\mathrm{glycine}$?

$Which\; of\; the\; following\; codons\; correspond\; to\; the\; amino\; acid\; lysine?$

$\text{Which of the following codons codes for the amino acid serine?}$

Which of the following is a set of $mRNA$ codons that code for the amino acid arginine?