Some jobs that are basically nurse will go through standard biology major sequence (usually if there isn’t a more focus prehealth major offered). Physicians assistant is an example. PA school happens after undergrad. A lot of people going to med school end ul taking standard biology majors. Arguably they should have been able to drop all those undergrad prerequisites and spend more time getting clinical hours vs toiling on ochem. As a crude input filter, medical schools often expect you to volunteer for these hours shadowing workers in the medical system even though you have to find the time yourself on top of a full major load that doesn’t account for these extracurricular expectations.