Effects of Nicotine and Carbon Monoxide in Smoke

Steps:

• Recall nicotine stimulates the cardiovascular system by increasing heart rate as a short-term effect.
• Recall carbon monoxide binds to hemoglobin more readily than oxygen, reducing oxygen transport.
• Match these to option A, which correctly describes both components.
• Eliminate other options for factual inaccuracies in effects or attributions.

Why A is correct:

• Nicotine acts as a stimulant on the sympathetic nervous system, elevating heart rate; carbon monoxide has 200–250 times greater affinity for hemoglobin than oxygen, per binding kinetics.

Why the others are wrong:

• B: Nicotine constricts small arteries; chronic bronchitis results from irritants like tar, not CO; CO binding is reversible.
• C: Reduced oxygen capacity affects blood transport, not short-term gas exchange; option is incomplete and misattributes.
• D: Goblet cell stimulation comes from smoke irritants, not nicotine/CO directly; clotting risk ties to other smoke components.

Final answer: A