Page 112 - The Manga Guide to Biochemistry

Cholesterol’s job

I understand that cholesterol is a type of steroid, but what exactly is a steroid? All I
know is that bodybuilders use them to get super buff.

Well, when we talk about “steroids,” it often brings to mind images of pharmaceuti-
cals and intimidating pectoral muscles, but there are actually a number of steroids
that exist in our bodies normally, like cholesterol.

For example, there is a type of hormone called a steroid hormone. The most
famous of these are the sex hormones—the indispensible hormones that make males
males and females females.

Sex hormones, eh? Whatever they are, I’m just glad they made me a girl. Boys are
totally gross!

Um...whatever you say, Kumi.
Anyway, testosterone, which is a sex hormone produced mainly in a male’s

testicles, is actually created with cholesterol as a raw material.
Progesterone, another sex hormone, is produced in a female’s ovaries or

placenta and is also created from cholesterol.
CH3

OH C=0

O O
Testosterone Progesterone

98 Chapter 3