Fafsa, Pell grant, financial aid

[allvia]

Since you already have an Associates, ASU should be only two more years - and with the Pell Grant (works as a tuition discount) is not a bad cost for a RA BS in Biology from a respected university.  Also, with your career plans a BS (vs a BA) is the way to go.

BS vs. BA makes no difference.

Speaking of BA vs. BS, I would recommend University of Florida's online BA over ASU's online BS because UF has a much better reputation in biology at the undergraduate level and a much better reputation overall. UF does have an online BS in Microbiology that might be more relevant to the work you want to do.

The OP is concerned about cost, the UF program you are speaking of is far more expensive at a $552 Per Credit cost https://ufonline.ufl.edu/tuition

Where I'm located a BS vs BA could matter in a STEM major, such as biology; it is possible in the southern US it would not impact one professionally.