Healthy men, women and children have a total of 639 muscles. It consists of about 6 billion muscle fibers, the longest is 60 cm, the shortest is only about 1 mm, the big muscle weighs 2000 grams, and the small muscle is only a few grams. The average person's muscle accounts for 35-45% of the body weight. The total length of capillaries in muscle can reach 654.38+ million kilometers, which can circle the earth twice and a half times.
The human body has 206 bones. There are 29 skulls, 5 trunk bones1and 4 femurs 126.
Everyone has 32 permanent teeth, and 28 really work.
Area ratio of upper and lower skin of human body
Head (hair, face and neck): 9%
Double upper limbs (upper arm, forearm, hand): 18%
Trunk (front and back, perineum): 27%
Lower limbs (including thighs, feet and buttocks): 46%
(5% for hand, 2 1% for thigh and 13% for calf)