I disagree. Exams are written in a way that demands application beyond simple recognition of the relevant concept. They do a good job of presenting unknown data which need to be analysed before an answer is prepared. The basic questions involve retelling of something that is memorised, but there aren't too many basic questions.
+1
Memorization is half the story. The next half involves analysis of the questions and using the right technique to answer the questions. Also, as there are lots of exceptions, it isn't common for people to lose marks.
If you memorize the whole book as your only preparation, you probably won't get an A+.
Even if you get an A+ for both the exams, it is still possible to get under 40. You could lose 20% or even more on the exam and still manage an A+.
In regards to the first thread, if you enjoy history, stick to it. If you decide to do biology, make sure you have the book Biozone Student Workbook 2011/2010.
Another factor to consider is that chemistry and biology have some topics which are related, such as the functional groups, proteins, DNA, electrophoresis and so forth.