Chapters 7 & 8 are Male Reproductive system and Female Reproductive system, respectively. Since I have used my reproductive system once, I am fairly certain I know what my parts are and how they generally work. I am not a male nor have I ever been one, but after reading the introduction to Chapter 7, I now know that "the function of the male reproductive system is to reproduce."
Um, okay. Here I was thinking this anatomy stuff was hard. It's obvious that the function of the male reproduction system is reproduction needs to be explained, but something like "Phimosis" would never need an explanation. (If you really must know, phimosis is congenital condition of tightening of the prepuce around the glans penis so that the foreskin cannot be retracted. Which took me several hours of research to figure that out.)