What term is used for an amino acid chain that has greater than 50 covalently linked amino acids?
a) Protein.
b) Peptide.
c) Amino acid.
d) Polypeptide.

In the following molecule, label a portion that shows only primary structure; label two types of secondary structure; circle the tertiary structure.

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Shown is the amino acid tryptophan. Put the letter “C” at the site of every carbon atom. Label the amino group, the carboxyl group, and the side group.

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The primary building blocks (monomers) of proteins are: 

a) Glucose molecules.

b) Lipids.

c) Nucleotides.

d) Amino acids.

e) None of these.

Which two functional groups are always found in amino acids?

a) Carbonyl and amino groups.

b) Carboxyl and amino groups.

c) Amino and sulfhydryl groups.

d) Hydroxyl and carboxyl groups.

The specific amino acid sequence in a protein is its:

a) Primary structure.

b) Secondary structure.

c) Tertiary structure.

d) Quaternary structure.

Which of the following is true of protein structure?

a) Peptide bonds are formed by hydrolysis.

b) Peptide bonds join the amine group on one amino acid with the R group of another amino acid.

c) Secondary protein structures are caused by hydrogen bonding between atoms of the peptide backbone.

d) Tertiary protein structure emerges when there is more than one polypeptide in a protein.

What is the role of a chaperone protein?

a) Assist in RNA and DNA folding.

b) Assist in membrane transport.

c) Assist in protein denaturation.

d) Assist in dehydration synthesis reactions.

e) Assist in protein folding or re-naturing.

DRAW IT The following diagram shows the bacteriorhodopsin protein. Indicate the regions of primary, secondary, and tertiary structure. Does this protein have quaternary structure?

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