this does not mean that you will go on growing and never stop. This is because, as your body makes new cells, old cells wear out. Another and more important reason is that there are certain organs in your body called glands. There are tear glands, sweat glands, oil glands, glands that help you digest your food, glands that help your heart to beat faster, glands that help you grow and so on. One such gland, called the pituitary gland, is like the captain of a ship. This fellow controls all the other glands, and orders them, 'Hey, guys! You must all work together!' Along will come a day when this smart gland, the pituitary gland, will tell all the other glands, 'You know, I think it is time you folks stopped. Just take it easy. This body has grown enough for now.' And by then, you will be somewhere between sixteen and twenty-three years old. By which time your legs will be about five times as long as they were when you were a baby, your arms will be about four times as long, and your head will be about twice as big. Surely, that is enough? Well, whatever you may think, your pituitary gland certainly thinks so!
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