What this page covers
Practice Step 1-style biochemistry questions on NO / cGMP / PDE5 inhibitors, including Syncope after nitrate use in a patient taking a newly prescribed medication highlights excessive cGMP signaling through the nitric oxide pathway, with emphasis on enzyme / mechanism and answer-choice reasoning.
How to use this page
Review the topic and reasoning focus, then practice Step 1-style questions inside BiochemStep. The question set emphasizes mechanism-first answer-choice reasoning rather than passive content review.