1. Which o the following is not a property of carbon?
a. Carbon-to-carbon bonds are limited to single bonds.
b. Carbon has 4 valence electrons
c.Carbon can form bonds to various other atoms.
d. Carbon-to-carbon bonds are strong.
2. Carbohydrate molecules:
a. Serve as structural components of human cell walls.
b. Form the regulatory compounds known as enzymes.
c. Are a source of energy.
d. Help protect vital organs from damage.
