Tag: zoology

Polycyclic aromatic hydrocarbons or PAHs are a group of powerful cancer-causing chemicals found in cigarettes that can damage DNA and set cells down the road to becoming tumours. PAHs tend to damage particular sections of DNA. We know that PAHs contribute to lung cancer in smokers because DNA damage can be seen at these sections in patients.  One PAH compound, benzopyrene, is notable for being the first chemical carcinogen to be discovered (and is one of many carcinogens found in cigarette smoke). Its consequences are so bad, even if the woman exposed to PAH pollution during pregnancy, then there is adverse birth outcomes including low birth weight, premature delivery and heart malformations, lower IQ and asthma. Cord blood of exposed babies shows DNA damage that has been linked to cancer.

Nicotine is found in the leaves of tobacco. It acts as both stimulant as it mimics the acetylcholine and also as the depressor. It stimulates passage of nerve impulses causes muscles to relax. 

Smoking is a practice in which a substance is burned and the resulting smoke breathed in to be tasted and absorbed into the bloodstream.
Emphysema is a form of chronic lung disease, usually caused by smoking.
Bronchitis is caused by tobacco smoke, dust, fumes, vapors and air pollution.
Changes in lung tissue begin when one inhale cigarette smoke.
Therefore, the correct answer is option D.

A substance that causes cancer is called a carcinogen. Cigarette smoke contains more than 4,000 chemicals out of which 43 are carcinogenic. Some of the carcinogens are nicotine, formaldehyde, benzene, carbon monoxide, etc. Most of the cigarette smoke remains in the lungs. This smoke damages the lung walls causing cancer. Thus the correct answer is option B.

Nicotine is a major constituent of tobacco, which plays a critical role in smoking addiction. In humans, nicotine is primarily metabolized to cotinine, which is further metabolized to trans-3'-hydorxycotinine.
Thus, the correct answer is option (C), 'Cotinine'.

Addiction is a phenomenon in which there is physical or psychological need to do, take or use something. The various addictions are smoking, chewing pan, chewing gutkha, alcohol, etc. Out of these addictions, the most harmful addiction for the respiratory system is smoking. It causes respiratory diseases like bronchitis, emphysema, laryngitis, breathlessnes, lung irritation. Its continuous use also causes permanent damage to the alveoli of the lungs. Nicotine is the addictive drug which is used in cigarettes.  

The largest cotton producing state in India is Gujarat. Cotton dust is defined as dust present in the air during the handling or processing of cotton, which may contain a fiber, bacteria, fungi, soil, pesticides and other contaminants which may have accumulated with the cotton during the growing, harvesting and subsequent processing or storage periods and causes hazardous effects on health while inhaling. So, cotton dust is an important pollutant here.

Carbon-dioxide is responsible for 'Global-Warming.
A layer of $CO _2$ in the atmosphere traps the infrared radiation coming from earth's surface. These trapped radiations heat the earth's atmosphere which results in green house effect and global warming.