If you are interested in field biology courses in upper years you may want to consider taking Enviro Sc 1B03. I heard it may be a prereq. for some upper year courses. Enviro Sc 1B03 is also a requirement for some of the courses in the Biology list. I would strongly recommend looking at what upper year courses you may want to take before choosing your electives.
If you have no interest definately don't bother with Env sc 1g03, or 1a03. Despite making you choose an area of science in first year, you are definately not stuck there.
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