The Wonders of the Human System

Erogenous zones are places on a woman's body that when touched cause her to become sexually aroused. There are many: the nape of the neck, the ears, the nipples, behind the knees, the inner thighs, the clitoris, the feet, and the lips. Of course, this is on a case by case basis; some women may be turned on by stimulation of other body parts as well.

Why do men have Adam's Apples?

Because they are constantly having to swallow their words! Sorry I just couldn't resist. Men have Adam's apples because of an enlarged thyroid cartilage. After puberty, a guy's thyroid cartilage continues to grow due to their testosterone levels, whereas a female's does not. It doesn't serve any purpose --- just a special characteristic of men.

Do twins have the same DNA?

Yes, identical twins do have the same DNA. There have been cases where DNA paternity tests have shown that two twin brothers were the father of one child. Cool, huh? While the DNA of identical twins is the same, it is expressed differently in each child. So for example, they do not have the same fingerprints because that element of their body developed differently. By the way, fraternal twins, made from two different eggs, do not have the same DNA.

Why does taking vitamins make your urine appear bright yellow?

The minerals and nutrients in some vitamins pass through your system and cause your urine to appear yellow. Usually this will happen if you take too many vitamins since your system doesn't need all of those minerals all at once.

How long can the average human hold their breath under water?

The Red Cross states that a human can comfortably hold their breath under water for 1-2 minutes. After that, it's a strain, and anything over three minutes can cause brain damage or worse. The record is 9 minutes 58 seconds held by free diver Tom Siestas.

What causes people to cry when they're sad?

It's hard to say why people cry emotional tears. Some believe that tears are full of hormones that are only produced when we're sad or stressed. Crying releases those hormones out of your body so that you can recover. So it may just be another way for the body to get rid of its "unwanted material."

How long does it take a pregnant woman's stomach to return to normal after birth?

By most accounts, it can take up to a month or more for a pregnant woman's belly to return to normal after giving birth. While it may not return to its original "splendor" on its own, you can help the situation by getting on an aggressive cardio plan and doing stomach tightening exercises.

How early does a baby have to be born to be considered premature?

A baby born before 37 full weeks is considered a preemie and will probably need to be closely monitored after its birth to assure that it develops properly.

What is the cause of sensitive teeth ?

Sensitive teeth usually occur when the gums start to recede from the teeth, causing roots to become more exposed. Whenever something hot or cold hits the root of the tooth, it reverberates throughout the nerves inside of the tooth causing excruciating pain in most cases.

Sources:

http://pregnancy.about.com/

http://www.saveyoursmile.com/healtharticles/sensitiveteeth.html

http://www.wisegeek.com/why-do-people-cry.htm

http://www.redcross.ca/article.asp?id=17582&tid=001

http://en.allexperts.com/q/Alternative-Medicine-991/urine-generally-bright-yellow.htm

http://www.thetech.org/genetics/ask.php?id=142

http://www.wisegeek.com/what-is-an-adams-apple.htm

http://www.menshealth.com/touchherhere/