What are facts for medical?

* The human heart beats an average of 100,000 times a day.

* The lungs hold about 5 liters of air.

* The brain uses about 20% of the body's total energy.

* The stomach can hold about 1 liter of food.

* The intestines are about 25 feet long.

* The kidneys filter about 1.3 liters of blood every minute.

* The liver weighs about 3 pounds.

* The skin is the largest organ in the body.

* The body contains about 60,000 miles of blood vessels.

* The human body is made up of about 100 trillion cells.