Heart: The average adult heart beats 72 times a minute; 100,000 times a day; 3,000,000 times a year; and 2.5 millon times a lifetime.
Lungs: The right lung is slightly larger than the left one. A human beign breaths about 22,000 times per day, breathing in 2100 to 2400 gallons of air each day.
Kidneys: Just one kideny is required to substitute two failed kideneys.The life extention of someone who donates a kidney is the similar as the general population.
Brain: The human brain is the fattest brain in the body and may consists of at least 60% fat.
Liver: The liver is the only organ that grows back.