The harm of cigarettes 1 cigarettes are also called cigarettes, which are very popular with men and boys. Some people say, "A cigarette afterwards is like a living fairy." Even adolescent students say, "If students don't smoke, they will fight on foot."
But do you know that there are three poisons in cigarettes, the first is nicotine, the second is tar, and the third is carbon monoxide. These three things are all necessary poisons for killing people!
When people start smoking, nicotine sneaks into the central nervous system of the human body, making smokers excited immediately, making them see that they are full of energy, and then fatigue is eliminated. These are some tricks that nicotine uses to hide itself. In fact, it will make people's cerebral cortex function degenerate and make their cerebral cortex function chaotic. Nicotine is the deadliest weapon of cigarettes. According to people's calculations, a little nicotine can kill a big mouse!
When nicotine is working, carbon monoxide is not idle. On the one hand, nicotine continues to destroy human brains and make them addicted. On the other hand, carbon monoxide invades human blood and combines with hemoglobin to form a kind of carboxyhemoglobin, which reduces the ability of blood to transport oxygen and causes myocardial hypoxia. At this time, someone will mistakenly think that they are anemic.
At this time, you should know that these three poisons attack the human body at the same time. When people start smoking, nicotine, carbon monoxide and tar stimulate the human nervous system, which will lead to vasospasm, increased heart rate, increased blood pressure, decreased cardiac output, dysfunction of ECG conduction system and other symptoms, and then cause arterial wall thickening, and then lead to arteriosclerosis, coronary heart disease and so on. If nicotine enters the human cerebral artery, it will also cause cerebral hemorrhage. Tar and carbon monoxide enter human lungs, which can induce bronchitis, lung cancer and other diseases.
According to scientists' calculations, every cigarette smoked will reduce life expectancy by 5 minutes, and every 13 seconds, one person on earth will die of tobacco-related diseases.
So, I warn you: quit smoking, everyone, he is your lifelong poison.
I have long heard that smoking is harmful to health. Not long ago, I saw on TV that May 3 1 was "World No Tobacco Day", and I was not reminded: How can cigarettes be harmful?
I happen to have nothing to do today, so let's do an inquiry experiment.
I remembered the methods I learned in related disciplines, and prepared 4 live fish, 4 small earthworms, 8 small bowls, 7 "Red Dragon" brand cigarettes and a wooden stick. I divided eight small bowls into two groups, numbered 1, 2, 3, 4 and A, B, C and D respectively. Put two cigarette shreds into bowls 1 and No.1, then put one cigarette shred into bowls 2 and 3, and then put half a cigarette shred into bowls 3 and 3. Finally, inject 50 ml of water into each bowl and stir with a wooden stick. After a while, the water in the bowl 1, 2, a and b turned yellow immediately, and there was an unpleasant smell. At this time, I put a live fish in bowls 1, 2, 3 and 4, and a small earthworm in bowls A, B, C and D, and then carefully observed the situation of fish and earthworm. An hour and a half later, the fish and earthworm 1 and A in the bowl died. After another half an hour, the fish and earthworms in bowls 2, 3, B and C died one after another, while the fish and earthworms in bowls 4 and D survived unharmed. Oh, cigarettes are really poisonous!
Through this experiment, I know that the survival time of small fish and earthworms is related to the amount of tobacco in the bowl: the more tobacco is put, the shorter their survival time is.
Later, I looked it up on the Internet: it is a well-known fact that smoking is harmful to health. Different cigarettes release different chemicals, but mainly tar, carbon monoxide, nicotine and other chemicals. Harmful substances produced by cigarette ignition can be roughly divided into six categories:
(1) Aldehydes, nitrides and alkenes can stimulate respiratory tract.
(2) Nicotine can stimulate sympathetic nerve and cause intimal injury.
(3) Amines, cyanide and heavy metals are all toxic substances.
(4) Radioactive substances such as phenylpropyl pyrene, arsenic, cadmium, methylhydrazine and aminophenol. These substances are carcinogenic.
⑤ Phenolic compounds and formaldehyde, etc. It has the effect of accelerating cancer.
(6) Carbon monoxide will reduce the ability of red blood cells to transport oxygen to the whole body.
Nicotine in tobacco is a neurotoxin, which mainly harms people's nervous system. After smoking, the sensitivity and accuracy of neuromuscular response are reduced. According to expert experiments, nicotine contained in cigarettes can poison a mouse. Nicotine in 20 cigarettes can poison a cow; The lethal dose of human is 50 -70 mg, which is equivalent to the nicotine content of 20-25 cigarettes. If nicotine in a cigar or three cigarettes is injected into a person's vein, it will kill him within 3-5 minutes. Carcinogens and promoters of tobacco tar are polycyclic aromatic hydrocarbons and porphyrins, which can be deposited in the lungs and may become cancerous after years of accumulation. The probability of lung cancer in 45-year-old smokers for 20 years is 10 times that of non-smokers.
At the same time, I also know that teenagers smoking is more harmful. This is because teenagers are in the period of growth and development, and their physiological systems and organs are not yet mature. Their resistance to harmful factors in the external environment is weaker than that of adults, and they are easy to absorb poisons and damage the normal growth of their bodies. Smoking damages the brain and affects intelligence.
Knowing this made me break out in a cold sweat. That's terrible! It's true: you don't explore, you don't know. If you explore, you will be shocked! When I arrive at school tomorrow, I must tell my classmates this conclusion, so that they can stay away from cigarettes and never smoke for life. At the same time, we should strive to be voluntary propagandists and say to all smokers, "For your own health and that of others, please don't smoke".