Talk about the top five items of the human body.

1. The most abundant part of human capillaries: scalp. 2. The most important life center of human body: medulla oblongata. 3. The most sensitive nerve reflex of human body: corneal reflex. 4. The smallest bone in the human body: the internal ear pedal bone. 5. The hardest part of human body: teeth. 6. The most flexible joint of human body: shoulder joint. 7. The most stable joint of human body: hip joint. 8. The most sensitive part of human touch: the tip of the index finger. 9. The most alkaline body fluid: pancreatic juice. 1. The most acidic body fluid in human body: gastric juice (acid). 11. The part with the strongest digestion and absorption function of human body: small intestine. 12. The largest cell in the human body: the egg cell. 13. The largest seed bone (free bone) in human body: patella. 14. The longest tubular bone in human body: femur. 15. The longest nerve fiber in human body: sciatic nerve. 16. The longest vein in human body: great saphenous vein. 17. The largest detoxification organ in the human body: the liver. 18. The most important internal organ of the human body: the heart. 19. The most basic way of human activity: reflection. 2. The most sensitive part of the human body to ischemia (hypoxia): the brain. Why don't I tell you the longest river in the human world-capillaries, whose total length is 15 times that of the Amazon River? Oh, that's enough weight, right?