At George Mason University, Introductory Biology I and II are NOT required for Biology majors either because they use Cell Biology, Animal Biology, and Plant Biology instead. Here's a simple scenario:
Let's say if I knew that I wanted to major in Biology right as I start college, then I would take Cell Biol my Freshman Fall semester and Animal Biol my Freshman Spring semester. Intro Biol I and II are not a prerequisite for Cell Biol. Once I have already taken Cell Biol, then I am no longer eligible to take Intro Biol for credit.
Now let's say if I did not know what I wanted to major in, so I decide to take Intro Biol I and II my Freshman year just to see if I like it or not. Later, if I decide to major in Biology, then they will count Intro Biol I and II as 8 Biology elective credits since a BA in Biology requires 32 Biology credits (45 for a BS in Biology) and the core classes required for the degree don't add up to 32 credits therefore you need to take additional Biology classes as electives.
At GMU, these are the major course requirements:
Cell Biol (w/ lab) - 4 credits
Animal Biol (w/ lab) - 4 credits
Plant Biol (w/ lab) - 4 credits
Microbiology - 3 credits
Microbiology Lab - 1 credit
Ecology (w/ lab) - 4 credits
Genetics (w/ lab) - 4 credits
Most other Biology classes taken count toward Biology elective credits. Biochemistry is not a required class but most people take it for the additional Biology credits. Human Anatomy & Physiology does not count toward Biology elective credits (specified in the course catalogue).
If I were you, go ahead and take Intro Biol II. Unless you just don't have the time and would rather take the core classes. Most of the time, if you have an undergrad degree in Biology, most Pharm schools will consider that enough for the General Biology requirement. Hope this helps a bit and is not confusing.