101. Why Does Fluoride Prevent Cavities?
Topics: what bacteria are and why they are so dangerous; what eggshells and teeth have in common; what fluoride is and how it prevents cavities
102. What Is a Computer Virus?
Topics: how a computer virus causes infection; the three stages of program infection; routes to protection
103. Why Do Divers Get the Bends?
Topics: why we can't breathe underwater; how a regulator helps scuba divers; the dangers of "the bends" plus treatment and prevention
104. Why Do Bears Hibernate and Humans Don't?
Topics: why humans must endure winter while bears and chipmunks can avoid it by hibernating
105. Why Do Clocks Go Clockwise?
Topics: what a stick and a piece of crystal have to do with telling time; how the clock was invented
106. What Causes Allergies?
Topics: why some people have allergic reactions but others don't; how the immune systems work or don't work; autoimmune disease
107. What Causes the Northern Lights?
Topics: how the earth resembles a giant magnet; the aurora borealis
108. Why Do Golf Balls Have Dimples?
Topics: how the golf ball evolved; why a rough ball travels further than a smooth one; impact of air; how to make objects more aerodynamic
109. Why Is It So Difficult to Stop Smoking?
Topics: why smoking is a powerful addiction; how it affects the chemistry of the brain; causes of withdrawal symptoms; attempts to escape addiction
110. How Do Microwave Ovens Cook Our Food?
Topics: why, if radio waves and microwaves both respond to being tuned, microwaves cook food and the radio can't; where water fits into the equation
111. Can a Human Voice Really Shatter Glass?
Topics: resonance; natural frequency of structures and objects such as glass; effects of resonance; attempts to shatter glass using a professional resonator--a trained singer
112. Why Does Food Rot?
Topics: microorganisms and how they work; the role of the freezer and refrigerator; different kinds of bacteria--good and bad; inevitability of food rotting
113. Why Does Getting Sick Always Give You the Same Symptoms?
Topics: how a cold or flu virus works; functions of congestion, a sore throat, sneezing and coughing; why we get sick more often in the winter; washing hands for prevention; comparison of a cold and flu virus; role of a fever; medication
114. Why Don't Skyscrapers Fall Over?
Topics: the evolution of the skyscraper; how high buildings can go; role of steel and steel frames; elevator's role in the "race for the sky;" challenge of wind; making a building flexible.
