Suppose you discovered a new amino acid. Its R-group contains only hydrogen and carbon atoms. Predict the behavior of this amino acid.

It is hydrophobic.

Proteins are polymers of _____.

amino acids

What type of bond joins the monomers in a protein's primary structure?

peptide

Which of these illustrates the secondary structure of a protein?

string with only two curls

The secondary structure of a protein results from _____.

hydrogen bonds

What name is given to the process seen in this animation?

dehydration synthesis

This animation illustrates the functioning of a _____ protein.

transport

Arrow A is indicating a(n) _____ protein.

structural

Arrow D is indicating a _____ protein.

receptor

Which of these does NOT contain a structural protein?

ovalbumin

Defensive proteins are manufactured by the _____ system.

immune

Which of the following best describes primary structure in proteins?

It is the sequence of amino acids in the complete protein.

An isomer of a particular molecule is

a molecule that has the same formula, but a different structure.

Classify these amino acids as acidic, basic, neutral polar, or neutral nonpolar.

basic: arginine
neutral polar: asparagine
neutral nonpolar: alanine

Classify these amino acids as acidic, basic, neutral polar, or neutral nonpolar.

acidic: glutamic acid
neutral polar: threonine
neutral nonpolar: tryptophan

At the pH found in cells (about 7.0), what happens to the carboxyl group on an amino acid?

It acts as an acid and loses a proton, giving it a negative charge.

Complete the following vocabulary exercise relating to the level of structure in proteins.

1. Quaternary structure is the result of two or more protein subunits assembling to form a larger, biologically active protein complex.
2. Secondary structure describes the alpha-helices and beta-sheets that are formed by hydrogen bonding between backbone atoms located near each other in the polypeptide chain.
3. Primary structure is the sequence of amino acids in a protein.
4. Tertiary structure is achieved when a protein folds into a compact, three-dimensional shape stabilized by interactions between side-chain R groups of amino acids.

Which one of the following is not a component of each monomer used to make proteins?

a phosphorous atom, P