Final answer:
Metaproterenol can be taken orally because it resists breakdown by COMT, allowing it to remain active when ingested. It is a bronchodilator, not an antibiotic like trimethoprim, and it has no connection to diseases such as tuberculosis or tularemia.
Step-by-step explanation:
Metaproterenol can be taken orally because it resists inactivation by catechol O-methyltransferase (COMT). COMT is an enzyme that breaks down catecholamines, a class of compounds that includes many bronchodilators.
Metaproterenol, a bronchodilator used to treat asthma and other conditions that result in constricted airways, is formulated to resist this breakdown. This resistance allows metaproterenol to have an effect when taken orally, providing therapeutic benefits for patients with respiratory conditions.
Unlike trimethoprim, an antimicrobial compound, metaproterenol is not an antibiotic and thus does not interfere with bacterial folic acid synthesis. Also, the question's mention of tRNA (which brings amino acids to the ribosome) and various diseases such as tuberculosis and tularemia does not pertain directly to the function of metaproterenol or the reasons why it can be taken orally.