Effects of Tobacco Smoke Components

Steps:

• Identify carbon monoxide's effect: binds to hemoglobin, forming a stable compound that impairs oxygen delivery.
• Identify nicotine's effect: stimulates the nervous system, increasing blood pressure and heart rate.
• Identify tar's effect: irritates respiratory tract, stimulating goblet cells to produce excess mucus.
• Match these to option B, which correctly describes all three without errors.

Why B is correct:

• Carbon monoxide forms a stable compound (carboxyhemoglobin) with hemoglobin, reducing oxygen transport; nicotine increases blood pressure; tar stimulates goblet cells, per respiratory physiology definitions.

Why the others are wrong:

• A: Carbon monoxide causes dizziness but not direct loss of consciousness; nicotine constricts vessels, doesn't destroy tar; tar coats cells.
• C: No "carbam" formation; nicotine constricts, doesn't dilate airways; tar narrows airways.
• D: Correct on carboxyhemoglobin but incomplete; nicotine increases heart rate (not specified); tar contains carcinogens but affects lung lining, not coronary artery directly.

Final answer: B