Final answer:
Carbon monoxide is highly toxic to aerobic organisms because it forms carboxyhemoglobin, which inhibits oxygen transport in the blood, and also binds to mitochondrial cytochrome c oxidase, disrupting the electron transport chain and ATP synthesis.
Step-by-step explanation:
Carbon monoxide (CO) is highly toxic to aerobic organisms because it disrupts cellular respiration.
This interference occurs due to CO's high affinity for the heme groups in hemoglobin, myoglobin, and mitochondrial enzymes such as cytochrome c oxidase (Complex IV of the electron transport chain).
When CO binds to hemoglobin, it forms carboxyhemoglobin, which prevents the hemoglobin from transporting oxygen.
Additionally, CO's binding to cytochrome c oxidase prevents the electron transport chain from functioning properly, which hinders the production of ATP—a crucial energy carrier in all cells.
Therefore, the correct answer is: B) It disrupts cellular respiration.
Comparably, cyanide also targets cellular respiration but does so by directly inhibiting cytochrome c oxidase, which stops the final electron transfer to oxygen, leading to a cessation of the electron transport chain and ATP synthesis.
This results in a type of hypoxia known as histotoxic hypoxia.
The effects of both CO and cyanide are detrimental to cellular functions and, consequently, can be lethal.