2. People's five senses capture all kinds of information all the time, but only 1% of the actual information is processed by the brain, and the remaining 99% are put in the "cold palace".
3. Each eye contains about 65.438+0.2 billion rod cells, which give people black-and-white vision and 7 million cone cells.
Under the ideal conditions at night, you can clearly see the match flame 80 kilometers away from the top of the mountain.
5. The length of human eyelashes is about 6 ~ 12mm, the upper eyelid is 100 ~ 150, and the lower eyelid is 50 ~ 75. Eyelashes will be constantly updated, and its average life span is 3 ~ 5 months.
6. There are 654.38+ million auditory nerve cells in the ear. After adjusting the sound, it is clearly transmitted to the brain, enabling people to distinguish various sounds. The human ear is most sensitive to the audio frequency of 2000 ~ 5000 Hz, and the baby's crying frequency is just within this range.
7. There are about 6.5438+million olfactory cells in the nose, each olfactory cell can smell 4,000 kinds of smells on average, and individual perfume experts can smell 654.38+00,000 kinds of smells at most.
8. Every 1 hill on the tongue contains 250 taste buds. There are 10000 taste buds on the tongue surface, and each taste bud consists of 50 ~ 70 taste cells. Taste cells are mainly divided into five types, which are sour, salty, bitter, spicy and sweet, but they are not "single-handed" but "coordinated".
9. The heart weighs about 260 grams and has a volume of 750 ml. During contraction, 70 ml of blood is injected into the blood vessel at a time, the output per minute is 5000 ml, and 7500 kg of blood is sprayed within 24 hours. The heart beats 60~ 100 times per minute. A person's life beats about 3 billion times.
10, lung, weighing about1000 ~1300g, and the ventilation of normal people is 4200~6600 ml per minute.
1 1. There are about 10~ 15 tons of food in a person's life, and 50~80 tons of water is processed by the stomach.
12. The liver weighs about 1300g and is the largest digestive gland in human body. Hepatocytes secrete about 100 ml bile every day, and can silently carry out more than 500 chemical reactions. Therefore, the liver is called the largest chemical plant in the human body.
13, kidney, weighing about 300 grams, consists of more than 4 million basic components-nephron, its inner tubule and length are about 50~60 mm, and the total area of microvilli near the glomerulus is 50~60 square meters. About 65,438+0,200 ml of blood passes through the kidney every minute, which can filter the whole body blood in about 27 minutes, catch nutrients that should not "leave the country" and discharge waste.
14. Normal kidneys produce about 120~ 140 ml of raw urine every minute, and the amount of raw urine produced every 24 hours is180l, of which 99% is absorbed, and 1% is final urine, and the amount is about/kloc-. Urine reaches the bladder through a 25 cm long sewer-ureter. If it accumulates to 400~500 ml, there will be urine.
15, duodenum. About 30 centimeters. In the past, people thought that this length was equivalent to the width of 12 fingers, hence the name.
About 40 tons of food and 348,000 cubic meters of air pass through the mouth and throat in a person's life.
17. Under normal circumstances, an adult will swallow 10 minutes for about 50 times. In 24 hours, a person swallows about 580 times. This is because even if we don't eat, we have to keep swallowing saliva secreted by our mouths.
18 I will swallow it 37 times an hour while sitting and reading. When you speak, your saliva will increase and the number of swallowing will increase. When a person is asleep, he will swallow 75 times an hour.
Our hands are well structured. One hand has 8 carpals, 5 metacarpals, 14 phalanges, 59 muscles and a well-developed neurovascular system.
20. Our hands are very hardworking. In a person's life, fingers must bend and stretch at least 25 million times. Even the baby lying in the crib bends down from time to time to fiddle with his fingers.
2 1, the total length of human small intestine is 5 ~ 8 meters, which can freely expand and contract in the body and can also contract at ordinary times.
22. The small intestine is wrinkled, with big wrinkles and small wrinkles, among which there are many protrusions. If the small intestine is carefully straightened, the total area of the inner wall of the small intestine is 200 square meters, which is equivalent to half a tennis court. It is more than enough to put a small wooden boat on it.
24. A person has more than 600 muscles. So some people call muscles the engine of the human body.
25. According to calculation, if the muscles of 6 square centimeters contract at the same time, they can lift 20 ~ 60 kilograms. If the 300 million muscle fibers in the whole body contract together in one direction, it will produce a force of 250,000 Newton (1 Newton is equivalent to 0. 1 kg force), which is equivalent to the weight that a crane can lift.
26. A person who is seven feet tall has more than 654.38 billion blood vessels. If they are connected end to end, the length is more than 65438+ million kilometers. You know, a circle around the earth is exactly 40 thousand kilometers. In other words, the length of human blood vessels can circle the earth for two and a half weeks.
Extended data:
After the age of 30, the body began to shrink gradually, but the shrinkage was very small, only seven thousandths of an inch a day. However, many a mickle makes a mickle. In another 20 years, you may be half an inch shorter. The total area of human skin is 1.8 square meters. Assuming that each square centimeter can bear the air pressure of 1 kg, then the whole skin will bear 18000 kg, that is to say, we men or women are poised with the weight of nine or ten big cars.
The thinnest skin on human body is 0.5mm, and the thickest skin is about 4 ~ 5mm (the thickness of palms and heels is about 4mm, while the thickness of eyelids and ears is only 0.5mm). The weight of human skin accounts for about 1/20 of the body weight. The skin of an adult has an area of about 2 square meters after deployment.
There are 14000 pores per square meter of skin. If these holes are connected one by one, you can make a 60-meter-long small tap water pipe. A person weighing 67 kilograms can only make 7 bars of soap with all his fat. Everyone loses their skin all their lives, and their total weight exceeds 227 kilograms.
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