Semi-related, since it involves a bad ISU professor:
My girlfriend (now wife) was a biology major. She breezed through Calc I (and learned a lot in the class) but her Calc II prof was just awful. She'd show me the stuff he gave out as assignments and I couldn't figure them out even though I'd had 3 semesters of Calc + Diff EQ at this point. I think he really just didn't want to teach Calc II and took it out on the students.
For her major, the requirement was intended to be take two semesters of calc or two semesters of statistics. I convinced her to drop the class and take Stat 101 next semester, as the catalog just said "two semesters of calculus or statistics from an approved list", not "two semesters of calculus or two semesters of statistics from an approved list". She checked with her advisor, who confirmed that the intent was two take a two-course sequence but acknowledged the loophole existed to take just Calc I and Stat I. So she ended up taking a blowoff stat course instead of retaking Calc II.
And that's why the Biology requirements changed from this in the 97-99 catalog:
View attachment 56715
To this in the 99-01 catalog:
View attachment 56716
I took a quick look at the current catalog and it now explicitly mentions one semester of each as a valid option, so at some point they backed off that stance.