3.5 Biological Molecules – Proteins

Question 1

a monomer of a protein

Answer 1

amino acid

Question 2

loss of shape in a protein that may be a result of changes in temperature, pH, or
chemical exposure

Answer 2

denaturation

Question 3

a catalyst in a biochemical reaction that is usually a complex or conjugated protein

Answer 3

enzyme

Question 4

a chemical signaling molecule, usually a protein or steroid, secreted by an endocrine
gland or group of endocrine cells; acts to control or regulate specific physiological processes

Answer 4

hormone

Question 5

describes a substance that dissolves in water; water-loving

Answer 5

hydrophilic

Question 6

describes a substance that does not dissolve in water; water-fearing

Answer 6

hydrophobic

Question 7

a covalent bond that forms between one amino acids carboxyl group and another
amino acids amino group

Answer 7

peptide bond

Question 8

a long chain of amino acids linked by peptide bonds

Answer 8

polypeptide chain

Question 9

a biological macromolecule composed of one or more chains of amino acids

Answer 9

protein

Question 10

a linear sequence of amino acids in a protein

Answer 10

primary structure

Question 11

association of different polypeptide chains in a protein

Answer 11

association of different polypeptide chains in a protein

Question 12

structure that proteins form by hydrogen bonding between the oxygen
atom of one amino acid and the hydrogen attached to the nitrogen atom of another amino acid

Answer 12

secondary structure

Question 13

a reactant that binds to a specific enzyme

Answer 13

substrate

Question 14

a protein’s three-dimensional conformation, including interactions between
secondary structural elements

Answer 14

tertiary structure