Hey.

You can't really diferentiate between two different courses. Bsc in chemistry is completely different form bsc in biology. If plants and animals , their anatomy and physiology is what interests you then go for biology. Else if the chemical composition of compounds and their empirical formulae surprises you the go for chemistry. If you are thinking about jobs afterwards then there are ample choices for both. Dont get confused. Do what pleases you. Hope this helps.