There are many danger of smoking to the body. A number of chemical additives are found in cigarettes. Some of them are classified as toxic and are not allowed in food.
One of the main dangers of smoking is due to nicotine is found naturally in tobacco. It has no odor and no color. It is however, both physically and psychologically addictive, and it causes those who use it to want to smoke one cigarette after another.
Nicotine enters the body as tiny droplets resting on particles of tar in cigarette smoke. Inhaled into the lungs, the drug passes quickly into the bloodstream, reaching the brain within about 10 seconds. In another 5 to 10 seconds the nicotine has spread to all parts of the body. The nicotine raises both the heart rate and blood pressure. The smoker quickly feels more alert and relaxed. In less than 30 minutes, however, about half of the nicotine has left the bloodstream, and the smoker starts feeling less alert, more edgy.
There is another danger of smoking as well. The tar from to tobacco smoke start to accumulate on the bronchial tubes leading to lungs.
The other danger of smoking is carbon monoxide. Smoking also increases the level of carbon monoxide in the lungs. This poisonous is quickly absorbed into the blood, reducing its capacity to carry oxygen. As a result, the smoker has to exert more physical effort to attain s given task than does a nonsmoker. The heart in particular must work hard, particularly during rigorous exercise. Increase levels of carbon monoxide in the blood can impair vision, perception of time, and coordination.
In brief, the chemical additives are dangerous. They cause smokers to worsen their health. A great number of smokers lose their lives because of the diseases resulting from smoking.
1. There are … chemical additives mentioned in
A. two B. three C. four
D. five E. six
2. What does the text mainly explain?
A. The danger of smoking
B. The victim of smoking
C. The reason why people smoke.
D. The substances that are found in tobacco.
E. Nicotine, the most dangerous
3. Paragraph 4 mainly explain that …
A. carbon monoxide causes death
B. carbon monoxide is dangerous
C. carbon monoxide is the most harmful
D. carbon monoxide is absorbed in lugs
E. people cannot get rid carbon monoxide