Includes index.

Why is my hair straight when my friend's hair is curly? -- How good is my memory? -- Why do things look all fuzzy when they get close to my eyes? -- Can my nose get tired of smelling things? -- Do people with big ears hear better than people with small ears? -- Why do I sometimes almost fall over? -- -- Why do things taste funny when I have a head cold? -- Why do I have spit? -- Why are my teeth different shapes? -- Does my skin ever fall off? -- Is milk good for my body? -- How much air do I take in when I breathe? -- What kinds of sounds does my heart make? -- How can I tell how fast my heart is beating? -- Are my fingerprints the same as my toeprints? -- If a mosquito is so tiny, how can I feel it land on me? -- Why does my tummy growl or grumble when I am hungry? -- What makes my tummy ache? -- Why does my knee jerk when the doctor taps it? -- How fast am I growing?