Which of the following BEST explains why carbon monoxide is dangerous to humans even at low concentrations?

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Question

Which of the following BEST explains why carbon monoxide is dangerous to humans even at low concentrations?

Accepted Answer

B. It binds to haemoglobin more strongly than oxygen does — Carbon monoxide binds to haemoglobin with an affinity approximately 200 times greater than oxygen, forming carboxyhaemoglobin. This prevents haemoglobin from carrying oxygen to body tissues, leading to oxygen deprivation and potentially death even at low concentrations.

Answer

A. It reacts with lung tissue to form carbonic acid

Answer

D. It dissolves in blood plasma blocking oxygen transport

Answer

C. It destroys the ozone layer reducing oxygen supply

Answer

B. It binds to haemoglobin more strongly than oxygen does

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