The Anatomy and Physiology of Animals/Test Yourselves/Chemicals Test Yourself/Test Yourself Answers

1. What is the difference between an atom and a molecule?

An atom is the simplest building block of matter – elements are made of atoms. Molecules are made of atoms joined together.

2. What is the chemical name for baking soda? And its formula?

Baking soda, NaHCO₃

3. Write the equation for carbonic acid splitting into water and carbon dioxide.

H₂CO₃ • CO₂ + H₂O

4. A solution of table salt in water is an example of an electrolyte. What ions are present in this solution?

Na+ and Cl^- (also H⁺ and OH^-)

5. What element is always present in proteins but not usually in fats or carbohydrates?

Nitrogen

6. List three differences between glucose and glycogen.

Glucose is a monosaccharide, glycogen is a polysaccharide (and a much bigger molecule); glucose is sweet to taste and dissolves in water, glycogen is not sweet and is insoluble; glucose is used for energy whereas glycogen stores energy.

7. Which will provide you with the most energy – one gram of sugar or one gram of butter?

Fats provide approximately 2.5 times more energy than carbohydrates – so the butter wins hands down!