CALS biology does have “pre-med” track, so either CALS or CLAS biology can work for pre-med. CALS and CLAS biology do share many of the same classes, taught by the same teachers. Best to compare curriculums and pick the one that works best for you.
CALS is a good option if you want the option of branching off into other fields (dual degree/minors, etc.) within CALS (same with CLAS). Eight UF programs are ranked in the top 10 in the world, from among more than 26,000 degree-granting institutions of higher education. Notice that the first 6 are in CALS: