Chapter 31

Contrary to popular belief, urine normally has no bacteria in it at all. Indeed, nary tract is one reason the kidneys and the bladder tend to stay free from infection - the flow of urine washes away any encroaching bacteria. Keeping this and the difference between male and female urethras in mind, why is it that women are more prone to bladder infections than men?

Suppose that instead of returning nearly all nutrients and 98 percent of fluids back into circulation, the kidneys could return only half these proportions. Could human beings function? How would it change the way they live?