It'd be nice if it were so black and white, but take this into consideration:
Once you're IN an undergraduate school, the curriculum/difficulty of the prerequisite classes varies very little from school to school. However, the ADCOMS might take into consideration what it took to get INTO a certain institution, and then "prorate" your GPA appropriately. For example, a 3.7 at a small state university would impress them less than a 3.7 at Harvard or MIT. Why? Not necessarily because Organic Chemistry is EASY at the state institution, but because more prestigious undergraduate schools are more selective about their admissions processes than a small state school would be, and someone that had the ability to get into a Harvard or MIT is showing that their academic prowess has a long track record of excellence. However, that being said, I would venture to say that there is actually very little scrutiny of an applicants' undergraduate schools' prestige going on.