#Question id: 160
#Unit 1. Molecules and their Interaction Relevant to Biology
Of the 20 standard amino acids, only ___________ is not optically active. The reason is that its side chain ___________.
#Question id: 161
#Unit 1. Molecules and their Interaction Relevant to Biology
Two amino acids of the standard 20 contain sulfur atoms. They are:
#Question id: 162
#Unit 1. Molecules and their Interaction Relevant to Biology
All of the amino acids that are found in proteins, except for proline, contain a(n):
#Question id: 163
#Unit 1. Molecules and their Interaction Relevant to Biology
Which of the following statements about cystine is correct?
#Question id: 164
#Unit 1. Molecules and their Interaction Relevant to Biology
The uncommon amino acid selenocysteine has an R group with the structure —CH2—SeH (pKa = 5). In an aqueous solution, pH = 7.0, selenocysteine would:
#Question id: 165
#Unit 1. Molecules and their Interaction Relevant to Biology
Amino acids are ampholytes because they can function as either a(n):