Unit 3 Chem of Life

Which Major Class of Bio-molecule is this?

• Carbohydrate

• Lipid

• Protein

• Nucleic Acid

Which specific type of Bio-molecule is this?

• triglyceride

• disacharide

• amino acid

• ATP

What is the function of this molecule?

• cellular energy

• energy storage

• energy transfer

• information storage

Ice floats on water because

• of cohesion.
• ice has a higher density than water.
• water shrinks when it freezes.
• water expands when it freezes.

Water molecules are polar, with the

• oxygen side being slightly positive and the hydrogen side being slightly negative.
• oxygen and hydrogen sides being slightly positive.
• oxygen and hydrogen sides being slightly negative.
• oxygen side being slightly negative and the hydrogen side being slightly positive.

In a water molecule, shared electrons spend more time around the oxygen atom than the hydrogen atoms. As a result, the oxygen atom is

• slightly negative.
• very negative.
• slightly positive.
• very positive.

A solution is a(an)

• combination of isotopes.
• chemical reaction.
• evenly distributed mixture of two or more substances.
• combination of two or more liquids.

A substance with a pH of 6 is called

• an acid.
• a base.
• both an acid and a base.
• neither an acid nor a base.

Solutions that contain concentrations of H⁺ ions lower than pure water

• have pH values below 7.
• are acids.
• are bases.
• are enzymes.

Amino acid is to protein as

• fat is to lipid.
• DNA is to RNA.
• sugar is to fat.
• simple sugar is to starch.