Free Effects of Smoking MCQs with Answers

• A. binds haemoglobin far more strongly than oxygen does and does not readily let go
• B. dissolves the walls of the alveoli
• C. destroys the red blood cells immediately
• D. prevents the diaphragm from contracting

Explanation: Carbon monoxide has roughly two hundred times the affinity of oxygen for haemoglobin and forms stable carboxyhaemoglobin, so those binding…

• A. tar
• B. carbon monoxide
• C. benzene
• D. nicotine

Explanation: Nicotine reaches the brain within seconds and acts on receptors there to give the reward that makes smoking so hard to give up, while also…

• A. the carcinogenic chemicals in tar
• B. the heat of the smoke
• C. nicotine acting on the brain
• D. the loss of surfactant from the alveoli

Explanation: Tar contains carcinogens such as benzopyrene that mutate the genes controlling cell division in the bronchial epithelium, and years of…

• A. the trachea is blocked by mucus
• B. the walls between alveoli break down, reducing the surface area for gas exchange
• C. the diaphragm is paralysed
• D. the blood contains too few white cells

Explanation: Smoke attracts phagocytes that release elastase, which digests the elastic tissue, so alveoli merge into large air spaces with much less…

• A. the alveoli fill with blood
• B. the ribs lose their cartilage
• C. smoke paralyses the cilia and stimulates extra mucus, which then collects in the airways
• D. the vocal cords are permanently inflamed

Explanation: Cilia that normally sweep the mucus escalator upwards are stopped by the smoke, while the irritation makes goblet cells secrete more…

• A. the smoke changes chemically once it leaves the smoker's lungs
• B. non smokers absorb nicotine through the skin
• C. it affects only people who are already ill
• D. sidestream smoke contains the same tar, nicotine and carbon monoxide, which bystanders inhale

Explanation: Smoke drifting from the burning tip is unfiltered and carries the same carcinogens, so people sharing the room inhale them and their risk…

• A. Emphysema
• B. Bronchoconstriction and inflammation
• C. Lung cancer
• D. Pneumonia

Explanation: Asthma involves bronchoconstriction, airway inflammation, and excess mucus production, causing wheezing and dyspnea.

• A. Cancer causing
• B. Pneumonia causing
• C. Emphysema
• D. Asthma

Explanation: Carcinogens are chemical or physical agents that can cause cancer by damaging DNA or disturbing the control of cell division.

• A. Carbon monoxide
• B. Methene
• C. Oxygen
• D. Nitrogen dioxide

Explanation: Carbon monoxide binds haemoglobin to form carboxyhaemoglobin, with an affinity about 200 to 250 times greater than oxygen, reducing oxygen…

• A. tuberculosis
• B. emphysema
• C. asthma
• D. cancer

Explanation: Long-term smoking commonly causes emphysema, in which alveolar walls are destroyed, reducing respiratory surface area and impairing gas…

• A. Tuberculosis
• B. Lungs cancer
• C. Asthma
• D. Emphysema

Explanation: Tuberculosis is caused by Mycobacterium tuberculosis and spreads between people, especially through airborne droplets, so it is…

• A. 5
• B. 90
• C. 15
• D. 10

Explanation: The question uses the conventional textbook figure that more than 10 compounds in tobacco tar contribute to cancer, so option d is…

• A. I only
• B. II only
• C. I and III
• D. II and III

Explanation: The correct answer is I and III. Emphysema is primarily caused by long-term exposure to airborne irritants, including tobacco smoke and…

• A. Lower levels of oxygen in the blood
• B. Higher levels of oxygen in the blood
• C. Lower levels of carbon dioxide in the blood
• D. No effect

Explanation: Emphysema can lead to decreased gas exchange efficiency in the lungs due to the destruction of alveoli.

• A. Bacterial infection
• B. Pollution
• C. Smoking
• D. Drinking
• E. Radiations

Explanation: Smoking is the most important cause of many respiratory disorders, including chronic bronchitis, emphysema, and lung cancer.

• A. 2
• B. 5
• C. 8
• D. More than 10

Explanation: Option A: There are more than 2 compounds in tar that are involved in causing cancer. The actual number is higher.

• A. Both of them follows
• B. None of them follows
• C. Only b follows
• D. Only a follows

Explanation: Statement a) "He will feel restlessness and anxiety" follows as quitting smoking can lead to withdrawal symptoms such as restlessness and…

• A. Asthma
• B. Tuberculosis
• C. Emphysema
• D. Both Options A and B are correct

Explanation: Emphysema is a lung condition that causes shortness of breath. In people with emphysema, the air sacs in the lungs (alveoli) are damaged.