Chapter 18: Electricity Martin Caon Examination Questions and Answers in Basic Anatomy and Physiology Third Edition

Martin Caon Examination Questions and Answers in Basic Anatomy and Physiology Third Edition Chapter 18: Electricity 1. Which is the correct statement about the behaviour of electrical charges? a. An electron and a proton will repel each other. b. Two like charges would repel each other. c. Like charges would attract each other. d. Unlike charges repel each other. Answer is B: Two positive charges would repel each other. Two negative charges will repel each other. So “like” charges repel. 2. If an ion has a positive charge, then what do we know about it? a. It will attract another ion with a positive charge. b. It has gained some protons. c. It has lost some electrons. d. It has more electrons than protons. Answer is C: An ion will have a positive charge when it has lost one or more electrons. Hence, it will have more protons in its nucleus than electrons in the orbitals. 3. Choose the alternative which correctly completes the following sentence: “There are two types of electric charge called: a. Protons and electrons and they attract each other”. b. Positive and negative and they attract each other”. c. Anions and cations and they repel each other”. d. Electrons and ions and they repel each other”. Answer is B: The two types of charges are positive and negative which may exist on a variety of particles such as those named in the other choices. 4. In the fluids of the human body, what are the carriers of charge that move through fluids called? a. Cations b. Ions c. Anions d. Electrons Answer is B: The charge carriers are ions (sometimes called electrolytes); they may have a positive or a negative charge. 5. Why is the human body (inside the skin) a conductor of electricity? a. It contains nerves and blood vessels which behave like electrical wires. b. Its solutions contain ions (electrolytes) which allow the body to conduct electricity. c. Muscle cells generate a voltage across their cell membrane, which produces current flow. d. Neurons generate a voltage across their cell membrane, which produces current flow. Answer is B: Na+ and Cl− are present in the blood, inside cells and in the interstitial fluid—they are the most common ions in the body. These and other ions/electrolytes, being charged particles, allow the body to conduct electricity. Choices C and D are not as good as B as muscle cells and n eurons produce a current flow when the cells depolarize. That is, when the voltage across their cell membrane changes. 6. What is one difference between static electricity and current electricity? a. Static electricity flows in the human body, while current electricity flows in electrical appliances. b. No useful purpose has been found for static electricity. c. In current electricity, charges are moving whereas in static electricity, charges do not move. d. Direct current involves static electricity, while alternating current involves current electricity. Answer is C: The word “current” means flowing while “static” means not moving.