Test Yourself

1. Hydrogen bonds are important in all of the following situations except ?
a. in stabilizing the secondary structure of proteins (Y/N)
b. in giving rise to hydrophobic interactions (Y/N)
c. in determining the three dimensional structure of glucose (Y/N)
d. in the tertiary structure of proteins (Y/N)
e. in the quaternary structure of proteins (Y/N)
The choice to which you answered NO should be the correct answer.

. Which of the following statements concerning hydrogen bonds is not correct?
a. they are easily broken under biological conditions
b. hydrogen bonds are not involved in van der Waal's attractions
c. they are involved in the hydration of monosaccharides
d. only water molecules can form hydrogen bonds with the amino acids of proteins
e. in general, hydrocarbons do not form hydrogen bonds

5. Under biological (aqueous) conditions, which of the following is not a property of ions?
a. in aqueous solutions they form electrostatic interactions with water molecules
b. they can be involved in determining the tertiary structure of proteins
c. they are important to the structure and function of phospholipids
d. they can pass through the plasma membrane by the process of simple diffusion
e. in a protein having many amino acids with ionic side chains, ionic bonds tends to destabilize the formation of protein secondary structure.

6. Ions that are dissolved in water ...
a. are always associated with proteins
b. are bonded to water molecules
c. do not affect the osmotic properties of the solution they are in
d. can pass through membranes by simple diffusion
e. are usually bonded to other ions by covalent bonds