Final answer:
The 35-year-old smoker's cravings and withdrawal are due to dependency on nicotine, which is a highly addictive substance found in cigarettes. Withdrawal can lead to physical and psychological symptoms, but nicotine replacement therapy may help to mitigate these effects, although long-term cessation is difficult to achieve.
Step-by-step explanation:
The craving and withdrawal symptoms that the 35-year-old cigarette smoker is experiencing are tied to nicotine dependency. Nicotine is a highly addictive substance found in tobacco products. It activates acetylcholine receptors, which play a significant role in arousal and reward mechanisms in the brain.
Withdrawal symptoms often include intense cravings, irritability, anxiety, headaches, sleep disturbances, and difficulty in concentrating.
Nicotine replacement therapies, like patches or gum, are used to alleviate these withdrawal symptoms, delivering nicotine without the harmful effects of tobacco smoke. However, even with these aids, many individuals find it challenging to quit smoking permanently.