Im going to be doing this course too, and from what I can gather they pretty much mean either Ext. 1 or Ext. 2 or both. I had the chance to look at the textbook and there was nothing in it to suggest MATH1001 was assumed knowledge.
Theres a chance you could struggle a little, but based on your mark in 2u its probably not going to be an issue. Maybe try and learn some 3u stuff outside of the bridging course?
Re: Should I do a biology unit to prepare myself for molecular biology? (first year s
You could do BIOL1001 which overlaps slightly with MBLG1001, AFAIK.
Ive heard BIOL1001 is much like a rehash of HSC biology.