Proteins & Nucleic Acids

Condensation of two amino acids forms a _______ and _______.

• Dipeptide and peroxy acid

• Oligopeptide and H+

• Dipeptide and water

• Oligopeptide and amide

1.  The repeating peptide bond and α-carbon is called the _______ of the amino acid chain.

• Backbone

• Spine

• Side chain

• . Variable chain

Which of the following amino acids produces an iminium salt (yellow precipitate) in a ninhydrin test.

• cystine

• tyrosine

• phenylalanine

• proline

What is the primary structure of a protein?

• Linear sequence of amino acids

• Secondary structure of amino acids

• Tertiary structure of amino acids

• Three-dimensional shape of amino acids

What is the side chain of the amino acid alanine?

• Hydrogen

• Methyl

• phenyl

• phenol

What is the side chain of the amino acid tyrosine?

• Hydrogen

• Methyl

• Phenyl

• Phenol

What is the side chain of the amino acid glycine?

• N

• C

• O

• H

What is the primary structure of a nucleic acid?

• Chain of amino acids

• Sequence of nucleotides

• Double helix structure

• Sequence of proteins

Which of the following amino acids is considered nonpolar?

• aspartic acid, glutamic acid, lysine, arginine

• serine, threonine, tyrosine, asparagine, glutamine

• histidine, glutamine, asparagine, serine

• glycine, alanine, valine, leucine, isoleucine, proline, methionine, phenylalanine, tryptophan, and cysteine (when not involved in disulfide bonds)

What is the side chain of the amino acid alanine?

• carboxyl group (COOH)

• methyl group (CH3)

• amino group (NH2)

• hydroxyl group (OH)