It's not just biology. It's basically every subject in high school. The amount of knowledge in the world has exploded in the last 100 - 150 years, yet our school system refuses to adapt and pretends we're still in the early 1900s. Back then you actually could get a good and reasonably in-depth overview of what makes the world work before going to college or work.

But those kinds of aspirations are completely futile these days. People in the ministries of education and other responsible bodies will argue that high school's purpose is not to educate on a subject in depth but to give a broad overview of many subjects but that's completely besides the point. Because the point is that the only way that they are able to "give you a broad overview" these days is by force-feeding you ever more facts and knowledge in sliced up classes, compressed into ever more shallow and boring text books and then letting you puke it all out in brain dead exams, many times a year for many different subjects, in parallel. Bulimia learning.

Which is beyond sad, because basically every subject can be the source of wonder and amazement if taught the right way and with enough time to explain and explore. Which is why we need to let our kids choose the subjects they are interested early in school and get comfortable with the fact that they won't have any knowledge about other subjects when they leave high school. There simply isn't any other way.