Regarding your second paragraph: I was fortunate to work in 3 fields in my scientific career: organic chemistry, materials science/organic semiconductors and molecular (synthetic) biology. This gave me ability to compare. What I found out, is that biology has the most interesting problems nowadays, and biology day-to-day work is extremely, outrageously, ridiculously stupid. I can not even start describing how amazingly debilitating molecular biology methods are. Right now, in the middle of the night I am stuck in the lab doing a day-and-half long protocol, all consisting on steps like "put liquid in", "pipette liquid out", "incubate for 5 minutes" and "shake for half hour".
Now here I am, after 15 years of school, 5 years of PhD and 11 years after that, doing work which is less intellectual than flipping burgers in McDonalds.
Fortunately, the fact that biology is so simple, gives me hope that it can be automated fairly easily, which I am planning to concentrate on for the next 5 years.
Please don't mix the plain complexity of life, which appears like "too many things to memorize", and complexity of mathematics and computer science, which is "understanding deep layers of abstractions". While I haven't taken intro bio classes, I read books and tons of papers. They are just plainly simple, you don't need brain to read them, you only need to memorize.