I've always wanted to know what are testicles made of? Is it fatty material, or what? Is it the same throughout, or is it different on the inside. What color are they? And what makes them so sensitive to pain?

Seriously

Here's a link.
http://www.bangla2000.com/Women's_World/Sex/Archive/8-16-2000/sex.html

Withdrawn

[This message has been edited by Genie (edited 03-06-2001).]

Here's a more detailed site. Takes time to load but it's good in explaining what they're made of.
http://handlin.cvm.okstate.edu/histology/MR/HiMRP2.htm

As to their extreme sensitivity, they're full of nerves, nature's way of reminding us to protect them although it seems to be a poor design to have such delicate organs hanging outside the body.

They have to be outside the body to be exactly one degree cooler than your body temperature for the production of sperm. I don't call that poor design.