There are the most extraordinary things going on in your body at any one time.
1 litre - that's how much gas humans produce on average each day.
It's produced in about 14 small pockets and the precise composition depends on the food you eat, how much air you swallowed that day, the types of bacteria in your intestines and how long you try to hold back the gas.
The smell is caused by small amounts of sulphur and nitrogen compounds created by partially digested food as well as the bacteria in the colon.
The sulphur compounds are mainly hydrogen sulphide (the gas that smells like rotten eggs) and mercaptan.
The nitrogen-rich compounds are mainly skatole and indole.
Sulphur-rich foods such as cabbage, eggs and meat cause smellier gases. Beans produce a lot of gas but the smell isn't as bad.
The pressure behind each pocket of gas in your colon is almost double the pressure in your car tyres.
Is the speed at which flu viruses are expelled when you sneeze. They can be propelled as far as 5m and infect everyone in their path.
An 'innie' or an 'outie'
Most people's bellybuttons are flat, form a small hollow and have a neat little crescent of skin above it.
The middle of the navel is usually connected on the inside to the outer stomach muscles.
If there's scarring between the navel and the muscle layer, the scar tissue and the small amount of fatty tissue under the skin push the bellybutton outwards.
If the navel protrudes a lot it might be because of an umbilical hernia, something that needs to be fixed - otherwise the small intestine might get caught in the gap in the stomach muscles.
The navel is what is eventually left behind after a baby's umbilical cord is cut just after birth.
Some people have more than two nipples
Did you know two per cent of women and one per cent of men have a third nipple or even more?
One woman had 10, all attached to full breasts.
The extra nipples are situated along the "milk lines" which run along both sides of the chest from the armpits through the normal nipple area down to the groin.
It might look like a mole or like a recognisable nipple and in rare cases could develop into a breast.
Celebs with extra nipples include actor Mark Wahlberg and singer Lily Allen.
If you have an extra nipple and it bothers you ask your doctor to remove it.
YOU Pulse; Spring, September 2007