i don't necessarily agree with this. i think it is ill advised to take anatomy and physiology without taking gen bio lol. i also think it's ill advised to take o chem your freshman year when you're still adjusting to college and are bound to be less efficient than your soph - sen years.
assuming bio major-
fresh year: Gen bio + Gen Chem + 2 other classes (i took required english course and Calc 1)
Soph Year: Advanced bio courses + O chem + 2 other classes
Junior Year: Advanced Bio courses + Physics + 2 other courses
by junior year, you will be thoroughly prepared for taking the DAT. Independent study will still be necessary, but by 21 you will be mature, developed, and ready to dedicate the necessary amount of time to succeed on the DAT.
And i think everyone on sdn can agree that the best piece of advice is to maintain the highest gpa possible. a bad college gpa isn't necessarily unsalvageable, but it is an absolute pain to continue education beyond the BS degree to fix it. good luck to you all. work hard.