Chemistry of Biology

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

Attractions between the negative Oxygen atom of one water molecule and the positive Hydrogen atom of another water molecule are called

• Covalent bonds
• Ionic bonds
• Polar bonds
• Hydrogen bonds

Why does ice float?

• As water freezes, it expands and its density decreases.
• As water freezes, it takes up more hydrogen from the atmosphere, causing it to have a greater buoyancy.
• As water freezes, air becomes trapped between the hydrogen bonds of water molecules.
• As water freezes, it takes up more oxygen from the atmosphere, causing it to have a greater buoyancy.

Which of the following is LEAST likely to dissolve in water?

• nonpolar fats and oils
• polar sugar molecules
• salt made of a positive sodium ion and a negative chloride ion
• all of the substances will dissolve easily in water

Large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. What is the reason for this phenomenon?

• Water is an acid.
• Water is a versatile solvent.
• Water has a high heat capacity.
•  Water acts as a buffer.

When a molecule has an opposite electrical charge on each end, it is known as what?

• cohesion
• polar molecule
• hydrogen bond
• solution

What about the chemical structure of water causes many of the critical properties that support life on Earth?

• Hydrogen Bonds

• Cohesive behavior

• Polarity

• Expansion Upon Freezing

Blood functions as a transport mechanism to take nutrients and oxygen to all cells in the body. What property of water allows for this to occur?

• Expansion Upon Freezing

• Universal Solvent

• Cohesive Behavior

• Ability to Moderate Temperature

This macromolecule make up cell membranes, store energy, and provide insulation

• carbohydrate

• lipids

• protein

• nucleic acid

This macromolecule carries hereditary information and instructions for building molecules

• carbohydrate

• lipids

• protein

• nucleic acid