Zoology of Class 12 is another interesting, yet simple approach. 

Conceptually, human reproduction is the heaviest chapter, and perhaps also the most important. Apart from that, Biotechnology is very high yield since very little content, gives you a lot of questions, and frankly, these notes are really good for these 3 chapters. In addition, the notes of human health and disease, have helped me even in my MBBS, no kidding, and thus, may be slightly on the higher side, but this chapter is frequently tested out of NCERT as well (example - there was a question on autoimmune disease), and I consider this chapter to be the reason why you chose to be a doctor and thus is a lovely read.

Conceptually - the notes cover Microbes in Human Welfare and Animal Husbandry as well, with a small section on Human Genetic Disorders such as Phenylketonuria.

Fair warning and disclaimer: A major missing chapter from the syllabus is that of Evolution (which is very important) and do not forget to read it from NCERT, which is where I read it from. Not too much extra is required for this chapter, and multiple reading of the NCERT would be more beneficial for this chapter.

The notes are organized as follows:

1.  Human Reproduction
2.  Reproductive Health: I didn't make notes for this chapter, but definitely, read the NCERT especially since there are some updates on the MTP act.
3.  Animal Husbandry - also read from NCERT 
4.  Biotechnology: Principles and Processes
5.  Biotechnology: Applications
6.  Microbes in Human Welfare - also read from NCERT
7.  Human Health and Disease
8.  Human Genetics and Disorders
9.  Major missing - Evolution; multiple readings from NCERT are a must

I have the following teachers to thank for their contribution to teaching these topics:

• Anil Tiwari sir (AT sir) - The majority of the Class 12 syllabus was taken up by sir, and he made it super simple and super engaging. Everyone loved studying the chapter on Reproduction from sir, it was so interesting, so clean, yet so funny!
• Jaimal Singh sir (JS sir) - Sir taught us a couple of chapters, and personally, they were the most crisp presentations of the chapters. He had a way of summarizing the entire NCERT into a couple of chapters.
• Chitresh Tiwari sir (CT sir) - Evolution was made very simple by sir, and he integrated the module and NCERT into a single revisable source. I had everything in my NCERT and remembered all the years, all the figures, all the facts and all the concepts. 
• Sanjeev Singh sir (SS sir) and Sanjeev Soti (SS sir) also played a great role by helping me clear out any doubts that I had from any topic.