30 Interesting facts about humans body !

 1. The surface area of the human lungs is approximately equal to the area of a tennis court.

2. During a person's lifetime, they spend about 2 weeks kissing.

3. The facial hair of a blonde-haired man grows faster than that of a man with dark hair.

4. Leukocytes in the human body live for two to four days, and erythrocytes for three to four months.

5. The strongest muscle in the human body is the tongue.

6. The human heart is approximately equal in size to that of a person's fist. An adult’s heart weights 220-260 grams.

7. At birth, there are 14 billion cells in the human brain. This number does not increase throughout a person's lifetime. After 25 years, the number of cells falls by 100,000 every day. About 70 cells die in the minute it takes you to read a page in a book. After 40 years, the decline of the brain accelerates sharply, and after 50 years neurons (that is, nerve cells) shrink and the brain gets smaller.

8. At birth, a child's body is made up of around 300 bones. But an adult has just 206.

9. During a person's lifetime, the small intestine is about 2.5 meters. After they die, the muscles in the walls of their intestine relax, and it's length increases to 6 meters.

10. Your right lung can take in more air than your left.

11. An adult person performs around 23,000 inhalations and exhalations a day.

12. The smallest cells in a man’s body are sperm cells.

13. There are about 40,000 bacteria in the human mouth.

14. Each of us has around 2,000 taste buds.

15. The human eye can distinguish 10 million different colours.

16. The chemical compound in the body which causes feelings of ecstasy (phenylethylamine) is also contained in chocolate.

17. The human heart pumps blood at such pressure that it would be able to raise blood up to the fourth floor of a building.

18. A person burns more calories when they are asleep than when they watch TV.

Children grow faster in the spring.

19. Every year more than 2 million left-handed people die because of mistakes they make when using machines designed for right-handed people.

20. It turns out that one man in every three hundred is capable of satisfying themselves orally.

21. A person uses 17 muscles when they smile, and 43 when they frown.

22. By the age of 60 most people lose half of their taste buds.

23. The rate at which a person's hair grows doubles during an airplane flight.

24. One percent of people can see infra-red light and 1% can see ultra violet radiation.

25. If you were locked in a completely sealed room, you would not die due to a lack of air, but from carbon dioxide poisoning.

26. Statistically, only one person out of two billion reaches the age of 116 years old.

27. On average, a person says 4,800 words in 24 hours.

28. The retinas inside the eye cover about 650 square mm and contain 137 million light-sensitive cells: 130 million are for black and white vision and 7 million are for helping you see in colour.

29. Our eyes remain the same size as they were at birth, but our nose and ears never stop growing.

30. In the morning, a person is about 8 millimetres taller than in the evening.